Hospital-Wide (All-Condition) 30‐Day Risk-Standardized Readmission Measure

DRAFT Measure Methodology Report

Submitted By Yale New Haven Health Services Corporation/Center for Outcomes Research & Evaluation (YNHHSC/CORE):

Leora Horwitz, MD, MHS Chohreh Partovian, MD, PhD

Zhenqiu Lin, PhD Jeph Herrin, PhD

Jacqueline Grady, MS Mitchell Conover, BA Julia Montague, MPH Chloe Dillaway, BA

Kathleen Bartczak, BA Joseph Ross, MD

Susannah Bernheim, MD, MHS Elizabeth Drye, MD, SM

Harlan M. Krumholz, MD, SM 

Contract number: HHSM-500-2008-0025I/HHSM-500-T0001, Modification No. 000005

Prepared For:

Centers for Medicare & Medicaid Services (CMS)

Last updated August 10, 2011

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TABLE OF CONTENTS

LIST OF TABLES .......................................................................................................................... 4

LIST OF FIGURES ....................................................................................................................... 5

GLOSSARY OF TERMS ............................................................................................................... 6

1. INTRODUCTION ...................................................................................................................... 7

1.1 Overview of Measure ...................................................................................................... 7

1.2 Hospital-wide Readmission as a Quality Indicator ......................................................... 7

1.3 Approach to Measure Development ............................................................................... 8

2. METHODS ................................................................................................................................ 9

2.1 Overview ......................................................................................................................... 9

2.2 Outcome Definition ....................................................................................................... 10

2.2.1 Planned readmissions ........................................................................................... 10

2.2.2 Thirty-day timeframe ............................................................................................. 14

2.2.3 All-cause readmission ........................................................................................... 17

2.3 Definition of Eligible Population .................................................................................... 17

2.3.1 Grouping patients into clinically coherent discharge condition categories by using AHRQ Clinical Classification System (AHRQ-CCS) ............................................................ 17

2.3.2 Inclusion / exclusion criteria .................................................................................. 18

2.4 Administrative Model Development .............................................................................. 20

2.4.1 Data sources ......................................................................................................... 20

2.4.2 Multiple models ..................................................................................................... 22

2.4.3 Models are defined by care team (service line) or clinical coherence ................... 22

2.5 Risk Adjustment ............................................................................................................ 24

2.5.1 Complications of hospitalization ............................................................................ 24

2.5.2 Case mix adjustment: risk variables ...................................................................... 25

2.5.3 Service mix adjustment ......................................................................................... 26

2.6 Statistical Approach to Model Development ................................................................. 26

2.6.1 Models for each cohort of conditions ..................................................................... 26

2.6.2 Hospital performance reporting ............................................................................. 28

2.6.3 Creating interval estimates .................................................................................... 28

2.6.4 Algorithm ............................................................................................................... 28

3. RESULTS ............................................................................................................................... 30

4. SUMMARY ............................................................................................................................. 32

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5. REFERENCES ....................................................................................................................... 33

6. APPENDIX – TABLES ............................................................................................................ 36

Appendix A – Top 10 primary discharge diagnoses for planned procedures ...................... 36

Appendix B – List of AHRQ procedure CCs defining the surgical/gynecological cohort...... 45

Appendix C – Condition categories assigned to the medical cohorts .................................. 48

Appendix D – Conditions that are treated as complications if occurring during index admission ............................................................................................................................. 54

Appendix E –Candidate risk variables ................................................................................. 56

Appendix F – Final risk-adjustment variables ...................................................................... 57

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LIST OF TABLES

Table 1 – Planned procedure list ................................................................................................ 12

Table 2 – Discharge condition categories considered acute or complications of care................ 13

Table 3 – Admissions, readmissions and mortality for the seven cohorts (2008) ....................... 24

Table 4 – Frequency of hospitals in each cohort (Number of hospitals = 4919) ......................... 31

Table 5 – Number of hospitals based on number of models to which they contribute ................ 31

Table 6 – C-statistic for each model ........................................................................................... 31

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LIST OF FIGURES

Figure 1 – Graphical representation of time to readmission ....................................................... 15

Figure 2 – Inclusion and exclusion criteria* ................................................................................ 21

Figure 3 – Distribution of 30-day hospital-wide readmission rates ............................................. 30

Figure 3a –Unadjusted rate ..................................................................................................... 30

Figure 3b –Risk-standardized rate .......................................................................................... 30

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GLOSSARY OF TERMS

Term Definition

Index admission Any eligible admission to an acute care hospital assessed in the measure for the outcome (readmitted or not within 30 days). (See Section 2.3.2)

Readmission An admission to an acute care hospital within 30 days of discharge from an acute care hospital. (See Section 2.2). A readmission may in turn serve as an index admission.

Planned readmission

An intentional readmission within 30 days of discharge from an acute care hospital that is a scheduled part of the patient’s plan of care. Planned readmissions are not counted as outcomes in this measure (see Section 2.2.1).

Discharge diagnosis ICD-9 level code of the principal reason for hospitalization.

Discharge condition category

A group of related discharge diagnosis ICD-9 codes, as grouped by the Agency for Healthcare Research and Quality (AHRQ) Clinical Classification Software (CCS).  (See Section 2.3.1).

Cohort

A group of admissions for patients with related condition categories or procedure categories; this measure includes seven cohorts, each with its own risk model (see Section 2.4.3).

Measure population The full set of admissions eligible for inclusion in the measure.

Procedure category A group of related procedure codes, as grouped by the Agency for Healthcare Research and Quality Clinical Classification Software (CCS) (see Section 2.4.3).

Risk variable

A variable in the risk-adjustment model intended to account for patient comorbid conditions or age. A risk variable may include multiple conditions. Each condition is a group of ICD-9 diagnosis codes, as defined by the Centers for Medicare and Medicaid Services Condition Category groups (CCs) (see Section 2.5.2).

Case mix The variation among hospitals in illness severity and age of their patients.

Service mix The variation among hospitals in the types of conditions they care for and procedures they provide.

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1. INTRODUCTION

1.1 Overview of Measure

Readmission following hospitalization is a costly and often preventable event. During 2003 and 2004, almost one-fifth of Medicare beneficiaries – over 2.3 million patients – were rehospitalized within 30 days of discharge.1 Jencks estimated that readmissions within 30 days of discharge cost Medicare more than $17 billion dollars annually.1 A 2006 Commonwealth Fund report estimated that if national readmission rates were lowered to the levels achieved by the top-performing regions, Medicare would save $1.9 billion annually. 2

Currently, the Centers for Medicare and Medicaid Services (CMS) publicly reports risk-standardized readmission rates for heart failure, pneumonia and acute myocardial infarction. 3-9 CMS has also developed hospital readmission measures for stroke and for hip and knee replacement, and is developing them for chronic obstructive pulmonary disease and vascular procedures. While it is helpful to assess readmission rates for specific groups of patients, these conditions account for only a small minority of total readmissions.10 By contrast, a hospital-wide, all-condition readmission measure could provide a broader assessment of the quality of care at hospitals. Therefore, CMS has contracted with Yale New Haven Health Services Corporation/Center for Outcomes Research and Evaluation (YNHHSC/CORE) to develop a claims-based, risk adjusted hospital-wide readmission (HWR) measure for public reporting that reflects the quality of care for hospitalized patients in the United States.

In this technical report we provide detailed information on the development of the HWR measure. Briefly, we developed the measure as an all-condition measure designed to capture unplanned readmissions within 30 days of discharge. The HWR measure complies with accepted standards for outcomes measure development, including appropriate risk adjustment and transparency of specifications. The measure includes all admissions except those for which a subsequent readmission would not be considered a quality signal. The measure does not count planned readmissions in the measure outcome, since they do not represent a quality signal. The overall risk-standardized readmission rate is derived from a composite of seven statistical models built for groups of admissions that are clinically related. The seven risk adjustment models will be tested for reliability in a split sample dataset combining two calendar years (2007 and 2008), and the stability of the measure over time will be tested using data from 2009. Although we developed the measure using Medicare data, the measure will also be tested in and adapted for all-payer datasets.

1.2 Hospital-wide Readmission as a Quality Indicator

Hospital readmission, for any reason, is disruptive to patients and caregivers, costly to the healthcare system, and puts patients at additional risk of hospital-acquired infections and complications. Readmissions are also a major source of patient and family stress and may

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contribute substantially to loss of functional ability, particularly in older patients. Some readmissions are unavoidable and result from inevitable progression of disease or worsening of chronic conditions. However, readmissions may also result from poor quality of care or inadequate transitional care. Transitional care includes effective discharge planning, transfer of information at the time of discharge, patient assessment and education, and coordination of care and monitoring in the post-discharge period. Numerous studies have found an association between quality of inpatient or transitional care and early (typically 30-day) readmission rates for a wide range of conditions. 11-18 Therefore, while readmission rates would never be expected to be zero, variation in readmission rates for a broad spectrum of conditions is related to quality of care. Furthermore, randomized controlled trials have shown that improvement in the following areas can directly reduce readmission rates: quality of care during the initial admission; improvement in communication with patients, their caregivers and their clinicians; patient education; predischarge assessment; and coordination of care after discharge.20-35 Evidence that hospitals have been able to reduce readmission rates through these quality-of-care initiatives illustrates the degree to which hospital practices can affect readmission rates. Successful randomized trials have reduced 30-day readmission rates by 20-40%.

Widespread application of these clinical trial interventions to general practice has also been encouraging. Since 2008, 14 Medicare Quality Improvement Organizations have been funded to focus on care transitions, applying lessons learned from clinical trials. Several have been notably successful in reducing readmissions within 30 days.36

Given that studies have shown readmissions within 30-days to be related to quality of care, and that interventions have been able to reduce 30-day readmission rates, it is reasonable to consider an all-condition 30-day readmission rate as a quality measure.

1.3 Approach to Measure Development

We developed this measure in consultation with national guidelines for publicly reported outcomes measures, consistent with the technical approach to outcomes measurement set forth in National Quality Forum (NQF) guidance for outcomes measures,37 CMS Measure Management System guidance, and the guidance articulated in the American Heart Association scientific statement, “Standards for Statistical Models Used for Public Reporting of Health Outcomes.”3 These standards include adequate risk adjustment and transparency. We are obtaining expert input during measure development, both through CMS and consultation with clinical and statistical experts. We are now soliciting comments from the general public via a public comment period.

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2. METHODS

2.1 Overview

We developed a hospital-wide 30-day readmission measure. This measure reports the hospital-level, risk-standardized rate of unplanned all-cause readmission after admission for any condition within 30 days of hospital discharge. The measure comprises a single summary score, derived from the results of seven different models, one for each of the following cohorts (groups of discharge condition categories or procedure categories): general medicine, surgery/gynecology, cardiorespiratory, cardiovascular, neurology, oncology, and psychiatry, each of which will be described in greater detail below. The measure uses one year of data.

We developed the measure in the Medicare fee-for-service (FFS) population age 65 and older discharged from any non-Federal short-stay acute care hospital or critical access hospital in the United States, excluding PPS-exempt cancer hospitals. The measure covers 95% of hospitalizations occurring in 2008 in this population, and includes 88% of readmissions following those hospitalizations. Hospitalizations were eligible for inclusion if the patient was enrolled in FFS Medicare Part A for 12 months prior and one month after the admission, if the discharge disposition was not to another acute care hospital, and if the patient was alive upon discharge. We excluded admissions for which we considered readmission not to be a signal of quality of care (patients who leave against medical advice, or have a discharge condition category with very high post-discharge mortality). To compare readmission performance across hospitals, we accounted for differences in patient characteristics (patient case mix) as well as differences in mixes of services and procedures offered by hospitals (hospital service mix).

To develop the measure, we analyzed admissions among Medicare FFS beneficiaries 65 and older who were discharged during 2008. The datasets were restricted to inpatient data, and included data on each patient for the 12 months prior to the index admission and the 30 days following discharge. We used the Agency for Healthcare Research and Quality (AHRQ) Condition Classification System (CCS) to group hospitalizations into clinically-coherent, mutually-exclusive condition categories according to their principal diagnosis.

We collapsed these discharge condition categories into seven major cohorts according to care teams (hospital service lines) and built a separate model for each one of these cohorts. We used hierarchical generalized linear models (HGLMs) to adjust for differences in hospital case mix and to account for the clustering of patients within a hospital. We adjusted for case mix differences among hospitals by risk-adjusting for patients’ comorbid conditions identified in inpatient episodes of care for the 12 months prior to the index admission as well as those present at admission. We did not risk-adjust for diagnoses that may have been a complication of care during the index admission. We used CMS Condition Category groups (CCs) to define the comorbid risk adjusters and used a fixed set of comorbid risk variables across models. We risk-adjusted for service mix differences

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among hospitals by including indicators for discharge condition categories (as defined by AHRQ CCS) in each model.

Finally, we used each of the seven models to calculate predicted and expected numbers of readmissions (as defined below in 2.6.1) for each hospital in each cohort. We then derived a single summary score from the results of the seven models by calculating the volume-weighted log average of the predicted over expected ratios from each model and multiplying the result by the average national readmission rate. This approach allowed us to take into account the variation in service mix across hospitals.

We evaluated the performance of the measure for various types of hospitals and groups of patients. We will test the reliability of the measure by randomly splitting combined 2007 and 2008 data and comparing the performance in each split sample. We will also test the measure’s stability over time by comparing 2008 and 2009 performance.

2.2 Outcome Definition

The outcome for this measure is unplanned all-cause 30-day readmission after an admission for any condition. We define a readmission as a subsequent inpatient admission to any acute care facility which occurs within 30 days of the discharge date of an eligible index admission. Any readmission is eligible to be counted as an outcome except those that are considered planned.

2.2.1 Planned readmissions

Readmissions may be either unplanned or planned. Unplanned readmissions are acute clinical events experienced by a patient that require urgent hospital management. Higher than expected unplanned readmission rates suggest lower quality of care and are the focus of quality measurement as part of quality improvement efforts. Because planned readmissions are not a signal of quality of care, we chose to exclude planned readmissions from the numerator. In order to do this, we developed an algorithm for identifying “planned readmissions” in claims data that will not count as readmissions in the measure. The algorithm was based on two main principles:

1. We define “planned” readmissions as those in which one of a pre-specified list of procedures took place (which will be described in detail below), or those for maintenance chemotherapy. Although other readmissions may be planned for medical reasons, these are rare and there is no reliable means of identifying them in administrative claims data. Maintenance chemotherapy is a common planned medical readmission that is reliably distinguishable in the data.

2. Admissions for acute illness or for complications of care are not “planned.” Even a typically planned procedure performed during an admission for an acute illness would not likely have been planned. We can identify readmissions as acute or non-acute by considering the principal discharge condition.

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We therefore developed an algorithm that uses procedure codes and discharge diagnosis categories for each readmission to identify planned readmissions. Readmissions that occur for planned procedures (listed below) and which are not for acute diagnoses or complications of care (listed below) are identified as planned.

The following examples illustrate this point:

Example 1: • A readmission with a discharge condition category of biliary tract disease that

included a cholecystectomy would be considered planned • A readmission with a discharge condition category of septicemia that included

a cholecystectomy would be considered unplanned • A readmission with a discharge condition category of “complications of surgical

procedures or medical care” would be considered unplanned

Example 2: • A readmission with a discharge condition category of coronary atherosclerosis

that included a percutaneous coronary intervention (PCI) would be considered planned

• A readmission with a discharge condition category of acute myocardial infarction that included PCI would be considered unplanned

Therefore, the HWR measure defines planned readmissions as any readmission that was either:

1. A non-acute readmission in which one of 32 typically planned procedures occurs

or

2. A readmission for maintenance chemotherapy

All other readmissions are considered unplanned and are counted as readmissions in the measure.

List of planned procedures

In order to develop a list of planned procedures, we reviewed the full AHRQ Clinical Classification System (CCS) procedure category list and identified 32 procedures that are typically planned and require an inpatient stay (Table 1). Readmissions in which any of these procedures are performed are considered planned if the discharge condition category is not acute or a complication of care.

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Table 1 – Planned procedure list

Data from 2008 MedPAR file, incorporating all final inclusion and exclusion criteria for the measure

AHRQ Procedure 

CC 

Procedure 

Readmissions without an acute diagnosis or a 

complication of care  

All readmissions 

Number  Percent  Number  Percent 

45 Percutaneous transluminal coronary angioplasty (PTCA) 

23,085  12.74  37,115  12.84 

84  Cholecystectomy and common duct exploration  15,405  8.5  17,868  6.18 Condition CCS 45 

Maintenance chemotherapy14,329  7.91  14,329  4.96 

157  Amputation of lower extremity 13,131  7.25  19,085  6.60 51  Endarterectomy; vessel of head and neck 11,569  6.38  12,411  4.29 78  Colorectal resection  11,522  6.36  20,004  6.92 44  Coronary artery bypass graft (CABG)  11,119  6.14  13,311  4.61 152  Arthroplasty knee  10,475  5.78  13,959  4.83 113  Transurethral resection of prostate (TURP) 7,909  4.36  9,150  3.17 153  Hip replacement; total and partial  5,694  3.14  22,803  7.89 211  Therapeutic radiology for cancer treatment 5,422  2.99  7,479  2.59 158  Spinal fusion  5,383  2.97  7,176  2.48 

48 Insertion; revision; replacement; removal of cardiac pacemaker or cardioverter/defibrillator 

5,313  2.93  43,432  15.03 

3  Laminectomy; excision intervertebral disc 5,172  2.85  6,541  2.26 36  Lobectomy or pneumonectomy 4,567  2.52  5,347  1.85 55  Peripheral vascular bypass  4,346  2.40  5,739  1.99 43  Heart valve procedures  4,133  2.28  4,863  1.68 52  Aortic resection; replacement or anastomosis 3,964  2.19  4,235  1.47 104  Nephrectomy; partial or complete 3,104  1.71  3,332  1.15 

60 Embolectomy and endarterectomy of lower limbs 

2,918  1.61  5,206  1.80 

85  Inguinal and femoral hernia repair 2,387  1.32  2,785  0.96 124  Hysterectomy; abdominal and vaginal 2,143  1.18  2,223  0.77 167  Mastectomy  1,419  0.78  1,475  0.51 154  Arthroplasty other than hip or knee 1,189  0.66  2,570  0.89 74  Gastrectomy; partial and total 1,174  0.65  1,541  0.53 114  Open prostatectomy  1,035  0.57  1,069  0.37 119  Oophorectomy; unilateral and bilateral 1,005  0.55  1,275  0.44 10  Thyroidectomy; partial or complete 986  0.54  1,069  0.37 64  Bone marrow transplant  458  0.25  468  0.16 166  Lumpectomy; quadrantectomy of breast 322  0.18  471  0.16 105  Kidney transplant  240  0.13  245  0.08 176  Other organ transplantation 171  0.09  263  0.09 ICD‐9  94.26, 94.27 

Electroshock therapy  114  0.06  139  0.05 

  Total  181,203     

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List of discharge condition categories that are acute or complications of care

According to our algorithm, admissions in which a planned procedure was performed are only considered “planned” if the patient was not admitted for an acute illness or complication of care. To develop a list of these acute and complication discharge condition categories, we reviewed the 10 most frequent discharge condition categories associated with each of our final set of 32 potentially planned procedures (Appendix A). From this set of 320 condition categories, we identified those which could be categorized as acute illnesses or complications of medical care. When a discharge condition category contained a mix of acute and chronic diagnoses, it was categorized as acute. Based on these criteria, we categorized 26 discharge condition categories as acute or complications of care, all listed within Table 2.

Table 2 – Discharge condition categories considered acute or complications of care

AHRQ CC 

Discharge condition categories that are acute or complications of care 

and are associated with planned procedures 

Number of 30‐day readmissions with this condition and a planned procedure 

100  Acute myocardial infarction 18328

237  Complication of device; implant or graft 11624

106  Cardiac dysrhythmias  10915

108  Congestive heart failure; nonhypertensive 5922

105  Conduction disorders  3663

146  Diverticulosis and diverticulitis 2322

2  Septicemia (except in labor) 2227

238  Complications of surgical procedures or medical care 1580

116  Aortic and peripheral arterial embolism or thrombosis 1427

   Fracture (207, 225, 226, 227, 229, 230, 231, 232) 1320

145  Intestinal obstruction without hernia 1134

201 Infective arthritis and osteomyelitis (except that caused by TB or sexually transmitted disease) 

630 

109  Acute cerebrovascular disease 595

97  Peri‐; endo‐; and myocarditis; cardiomyopathy  550

122  Pneumonia (except that caused by TB or sexually transmitted disease)  431

245  Syncope 287

127  Chronic obstructive pulmonary disease and bronchiectasis 248

131  Respiratory failure; insufficiency; arrest (adult) 232

55  Fluid and electrolyte disorders 229

159  Urinary tract infections  161

130  Pleurisy; pneumothorax; pulmonary collapse 154

157  Acute and unspecified renal failure 115

139  Gastroduodenal ulcer (except hemorrhage) 91

153  Gastrointestinal hemorrhage 89

160  Calculus of urinary tract 74

112  Transient cerebral ischemia 30

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  All condition categories 64,378

We quantified the impact of our decisions regarding the definition of planned readmissions on readmission rates. In 2008, there were 181,203 planned readmissions, accounting for 12% of all readmissions.

2.2.2 Thirty-day timeframe

We considered 30 days as a clinically reasonable timeframe for multiple reasons:

1) Within a 30-day time frame, readmissions are more likely attributable to care received during the index hospitalization and during the transition to the outpatient setting. A number of studies have demonstrated that improvements in care at the time of patient discharge can reduce 30-day readmission rates.20,21,23,28-35,38 Hospitals, in collaboration with their medical communities, can take a number of actions to reduce readmissions: ensure patients are clinically ready at discharge; reduce risk of infection; reconcile medications; improve communications among providers involved in transition of care; encourage strategies that promote disease management principles; and educate patients about symptoms to monitor, whom to contact with questions, and where and when to seek follow-up care.20,21,23,28-35,38

2) The 30-day timeframe is consistent with the other readmission measures approved by the National Quality Forum (NQF) and publicly reported by CMS.

3) In addition to clinical judgment, we reviewed “time to event” curves of readmission over time to decide whether 30-day readmission is a quality signal. The readmission “time-to-event curves” showed a very similar pattern for all these discharge condition categories: a rapid early accrual of readmissions, with a stable and consistent readmission rate thereafter. Curves typically stabilized within 30 days of discharge, indicating that a 30-day cutoff is clinically reasonable. Time-to-event curves for the most common conditions are shown in Figure 1.

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Figure 1 – Graphical representation of time to readmission

 

 

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2.2.3 All-cause readmission

We defined the outcome as “all-cause” unplanned readmissions rather than readmissions related to the previous hospitalization for multiple reasons. First, from the patient perspective, readmission for any reason is likely to be an undesirable outcome of care. Furthermore, readmission for any reason exposes the patient to risks associated with hospitalization, such as iatrogenic errors. Second, there is no reliable way to determine whether a readmission is related to the previous hospitalization based on the documented cause of readmission. For example, a stroke patient who develops aspiration pneumonia may ultimately be readmitted for respiratory distress. It would be inappropriate to treat this readmission as unrelated to the care the patient received for stroke. Third, the range of potentially avoidable readmissions also includes those not directly related to the index condition category, such as those resulting from medication reconciliation errors, poor communication at discharge, or inadequate follow-up post-discharge. Creating a comprehensive list of potentially avoidable readmissions related to the previous hospitalization’s condition category would be arbitrary and, ultimately, challenging to implement. Fourth, all existing CMS readmission measures report all-cause readmission, making this approach consistent with existing measures. Fifth, research shows that readmission reduction interventions can reduce all-cause readmission, not only condition-specific readmission. Finally, defining the outcome as all-cause readmissions may encourage hospitals to implement broader initiatives aimed at improving the overall care within the hospital and transitions from the hospital setting instead of limiting the focus to a narrow set of condition-specific approaches. The goal of this measure is not to reduce readmissions to zero, but to assess hospital performance relative to what is expected given the performance of other hospitals with similar case mixes.

2.3 Definition of Eligible Population

Our guiding principle for defining the eligible population was that the measure should capture as many unplanned readmissions as possible across a maximum number of acute care hospitals. Therefore we included in the measure all admissions except those for which full data was not available or for which 30-day readmission cannot reasonably be considered a signal of quality of care.

2.3.1 Grouping patients into clinically coherent discharge condition categories by using AHRQ Clinical Classification System (AHRQ-CCS)

For our previous claims-based condition- and procedure-specific outcomes measures we have used individual ICD-9 codes or CPT codes of the index admission to define the cohort. For the HWR measure, using ICD-9 codes would have been very impractical because there are potentially thousands of ICD-9 codes that would have to be included. Therefore, we aggregated ICD-9 codes into clinically coherent conditions.

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To aggregate these codes, we chose the Agency for Healthcare Research and Quality’s Clinical Classifications Software (CCS). We selected CCS because 1) it is well-known and widely used, 2) it is based on the principal diagnosis and not on complications or events that occur during hospitalization (unlike the Medicare Severity Diagnosis Related Groups [MS-DRGs]), and 3) because the groups of ICD-9 codes within each category are more clinically homogenous than other available groupers (MS-DRGs and CMS Condition Categories) and have relatively similar readmission rates. AHRQ CCS has been used by managed care plans, insurers and researchers for a variety of functions, such as assessing resource use, predicting future expenses, comparing procedure or condition rates among payers or hospitals, or profiling patients. There are a total of 285 mutually exclusive AHRQ condition categories, most of which are single, homogenous diseases such as pneumonia or acute myocardial infarction. Some are aggregates of conditions, such as “other bacterial infections.” Mental health and substance abuse categories are included. In addition, AHRQ provides 231 mutually exclusive procedure categories to group procedures a patient might have had during hospitalization.

2.3.2 Inclusion / exclusion criteria

Admissions are eligible for inclusion in the measure if:

i. Patient is alive upon discharge Rationale: Patients who die during the initial hospitalization cannot be

readmitted.

ii. Patient is not transferred to another acute care hospital upon discharge Rationale: In an episode of care in which patient is transferred among

hospitals, responsibility for the readmission is assigned to the final discharging hospital. Therefore these intermediate admissions within a single episode of care are not eligible for inclusion.

iii. Patient is 65 or older Rationale: Younger Medicare patients represent a distinct population with

dissimilar characteristics and outcomes.

iv. Patient has at least 30 days of post-discharge enrollment in FFS Medicare or died within the 30-day post-discharge period

Rationale: This is necessary in order to identify the outcome (readmission) in the dataset.

v. The admission is not to a PPS-exempt cancer hospital Rationale: These hospitals care for a unique population of patients that is

challenging to compare to other hospitals. .

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These inclusion criteria are consistent with existing CMS publicly reported measures for readmission except for the final one, which is unique to the HWR measure.

We then applied several exclusion criteria to the measure population. The first two are consistent with existing measures; the remainder are unique to the HWR measure.

a. Patients not continuously enrolled in FFS Medicare for the 12 months prior to the index admission are excluded Rationale: This is necessary to capture historical data for risk adjustment

b. Patients discharged against medical advice (AMA) are excluded

Rationale: Hospital had limited opportunity to implement high quality care  c. Admissions for “rehabilitation care; fitting of prostheses and adjustment

devices” (CCS 254) are excluded Rationale: These admissions are not for acute care or to acute care hospitals

d. Patients admitted for a condition category with high competing mortality risk

in the post-discharge period are excluded. A “high competing mortality risk condition category” is one for which there were more patients who died post-discharge without being readmitted than there were patients who were readmitted.

i) One condition category met this criteria for all cohorts: • Malignant neoplasm without specification of site (CCS 43)

ii) Several condition categories met this criteria only for the cancer and medicine cohorts (that is, admissions in the surgical cohort with these conditions were not excluded): • Melanomas of skin (CCS 22) • Cancer of breast (CCS 24) • Cancer of colon (CCS 14) • Cancer of liver and intrahepatic bile duct (CCS 16) • Cancer of pancreas (CCS 17) • Secondary malignancies (CCS 42) • Cancer of bronchus, lung (CCS 19) • Cancer of other male genital organs (CCS 31) • Cancer; other and unspecified primary (CCS 41) • Fracture of neck of femur (hip) (CCS 226) • Cancer of ovary (CCS 27)

Rationale: A high ratio of post-discharge deaths per readmissions reduces the opportunity for readmissions and interferes with the readmission quality signal. In addition the quality signal may be dwarfed by the unavoidable severity of illness.

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2.4 Administrative Model Development

2.4.1 Data sources

To develop the measure, we constructed a dataset that contains administrative hospitalization data for fee-for-service (FFS) Medicare beneficiaries, 65 and older on admission, hospitalized in 2008. The dataset also includes data on each patient for the 12 months prior to the index admission and the 30 days following discharge. We obtained index admission, readmission, and in-hospital comorbidity data from the Medicare Provider Analysis and Review (MEDPAR) file. Enrollment and post-discharge mortality status were obtained from the Medicare Denominator file, which contains beneficiary demographic, benefit, coverage, and vital status information.

Comorbidities were assessed using data from the index admission and any admission in past year. The Medicare outpatient (Part B) data were not included because 1) this was technically cumbersome, and 2) it would make expanding the measure later to an all-payer population very difficult (all-payer data typically includes only data for hospitalized patients).

The final measure population is shown in Figure 2.

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Figure 2 – Inclusion and exclusion criteria*

*Based on 2008 MedPAR data

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2.4.2 Multiple models

Because the risk of readmission varies with patient factors, including age and comorbidities, hospital comparisons using readmission rates need to account for differences in these factors. To adjust for such “case mix” differences we used regression analysis. Rather than assume that effect of risk factors would be homogeneous across all discharge condition categories, we assessed the performance of a single model versus multiple models. Our analyses showed consistently that a single model did not perform as well as multiple models, independently of how we defined the multiple models. The multiple models approach showed better discrimination and predictive ability for readmission risk.

The risk of readmission also varies according to the mix of conditions and procedures at a hospital (service mix). A multiple models approach better captures these variations. Finally, dividing the measure into several models may increase the practical utility of the measure by providing actionable information to hospitals.

2.4.3 Models are defined by care team (service line) or clinical coherence

In this step we organized admissions into seven mutually exclusive cohorts: general medicine, surgery/gynecology, cardiorespiratory, cardiovascular, neurology, oncology, and psychiatry. We built a separate model for each cohort.

a) Rationale: We expect the hospital component of readmission risk to be in part related to the care provided by a team of doctors, nurses, care coordinators, pharmacists, etc. Conditions typically cared for by the same team of clinicians would therefore be expected to experience similar added (or reduced) levels of readmission risk. Therefore, we grouped discharge condition categories typically cared for by the same group of clinicians into six cohorts: medicine, surgery, cardiovascular, neurology, oncology and psychiatry. Organizing results by care team (service line) in this way will allow hospitals to identify areas of strength and weakness if the results of each component model are reported separately.

b) Approach to individual cohorts:

i. Surgical/gynecology. This cohort includes admissions likely cared for by surgical or gynecologic teams. We used AHRQ procedure categories (rather than AHRQ condition categories) to identify these patients. We reviewed the list of AHRQ CCS procedures and identified those which could typically result in surgical or gynecological teams caring for the patient. Minor procedures that would not have required a patient to be on the surgical service were not included in the list (for example: breast biopsy). Procedures that would generally accompany other, more major, procedures were also not included in the list on the assumption that patients undergoing these procedures would also undergo another procedure on the list (for example, intraoperative cholangiogram). The full

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list of procedures assigned to the surgical/gynecology cohort is summarized in Appendix B. We will consult surgeons from various specialties to confirm our list of surgical procedures. Any admission during which a procedure from the final list was performed was assigned to the surgical/gynecology cohort.

ii. Cardiorespiratory. This cohort includes several conditions with very high readmission rates – pneumonia, chronic obstructive pulmonary disease, and heart failure – as well as admissions for other condition categories related to these three (asthma, acute bronchitis, pulmonary heart disease, and respiratory failure). We combined these patients into a single cohort because patients with these diseases are often clinically indistinguishable, are typically treated by the same care teams, and are often simultaneously treated for several of these diagnoses.

iii. Cardiovascular. This cohort includes cardiovascular condition categories such as acute myocardial infarction that in large hospitals might be cared for by a separate cardiac or cardiovascular team.

iv. Neurology. This cohort includes neurologic condition categories such as stroke that in large hospitals might be cared for by a separate neurologic team.

v. Oncology. This cohort includes medical admissions for cancer treatment. Patients with cancer diagnoses who undergo eligible surgical procedures (for example, a patient with a colon cancer diagnosis who undergoes a colectomy during hospitalization) are assigned to the surgical cohort.

vi. Psychiatry. This cohort includes admissions with primary psychiatric condition categories.

c) Assignment of admissions to cohorts

i. Admissions are first screened for the presence of an eligible surgical procedure category. Admissions with any of these procedures are assigned to the surgical cohort, regardless of the diagnosis code of the admission.

ii. All remaining admissions are assigned to cohorts on the basis of the discharge condition category. The AHRQ procedure categories for the surgical cohort are shown in Appendix B. The AHRQ discharge condition categories for the medical groups are shown in Appendix C.

Summary results for the seven cohorts are shown in Table 3.

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Table 3 – Admissions, readmissions and mortality for the seven cohorts (2008)

Model Group Admits Unplanned

Readmits

Unadjusted Unplanned

30-Day Readmit

Rate

Deaths Without Readmit

30-Day Death Rate

Without Readmit

Planned Readmits

Unadj. Planned 30-Day

Readmit Rate

% Readmits that are Planned

Cardio-vascular 843,373 129,896 15.4% 22,118 2.6% 25,731 3.1% 17%

Cancer 82,394 20,616 25.0% 11,009 13.4% 14,587 17.7% 41% Cardio-respiratory 1,405,271 299,275 21.3% 74,619 5.3% 16,867 1.2% 5%

Medicine 3,009,835 549,935 18.3% 150,082 5.0% 59,209 2.0% 10% Neurology 459,189 68,000 14.8% 30,276 6.6% 8,176 1.8% 11% Psychiatry 89,859 14,225 15.8% 3,942 4.4% 829 0.9% 6%

Surgical 2,163,433 275,329 12.7% 37,685 1.7% 55,804 2.6% 17%

Total 8,053,354 1,357,276 16.9% 329,731 4.1% 181,203 2.3% 12%

2.5 Risk Adjustment

The goal of risk adjustment is to account for differences across hospitals in patient demographic and clinical characteristics that might be related to the outcome but are unrelated to quality of care. Risk adjustment for this measure is complicated by the fact that it includes many different discharge condition categories. We must therefore adjust both for case mix differences (clinical status of the patient, accounted for by adjusting for comorbidities) and service mix differences (the types of conditions/procedures cared for by the hospital, accounted for by adjusting for the discharge condition category). Consistent with NQF guidelines, we did not adjust for socioeconomic status, gender, race, or ethnicity because hospitals should not be held to different standards of care based on the demographics of their patients. We did not adjust for patients’ admission source or discharge disposition (e.g. skilled nursing facility) because these factors are associated with structure of the health care system, and may reflect the quality of care delivered by the system.

2.5.1 Complications of hospitalization

Complications occurring during hospitalization are not comorbid illnesses, may reflect hospital quality of care, and therefore should not be used for risk adjustment. Although adverse events during hospitalization may increase the risk of readmission, including them as covariates in a risk-adjusted model could attenuate the measure’s ability to characterize the quality of care delivered by hospitals. CORE has previously reviewed every CMS Condition Category (CMS-CC) and identified those which, if they occur during the index hospitalization, would be considered potential complications rather than comorbidities. For example: fluid, electrolyte or base disorders; sepsis; and acute liver failure are all examples of CCs that could potentially be complications of care (see Appendix D for the complete list). For the HWR measure, we applied this pre-established list to all

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potential risk variables. CCs on this list were not counted as a risk factor in our analyses if they appeared only on the index admission.

2.5.2 Case mix adjustment: risk variables

We used CMS-CCs, the grouper used in previous CMS risk-standardized outcomes measures, to group ICD-9-CM codes into risk adjustment variables, since four CMS condition-specific claims-based readmission models that use this grouper to define variables for risk adjustment have been validated against models that use chart-abstracted data for risk adjustment. 5,7,8 We decided to use a fixed, common set of variables in all our models for simplicity and ease of data collection and analysis. We describe below the steps for variable selection:

a. We developed a “starter” set of 30 variables drawn from previous readmission measures (AMI, heart failure, pneumonia, hip and knee arthroplasty, and stroke). In many cases, these variables included multiple CMS-CCs each

b. Next we reviewed all the remaining CMS-CCs and determined on a clinical basis whether they were likely to be relevant to an all-condition measure. We selected 11 additional variables to consider. (See Appendix E for complete set of starter variables).

c. Using data from the index admission and any admission in the prior 12 months, we ran a standard logistic regression model for every discharge condition category with the full set of candidate risk adjustment variables. We compared odds ratios for different variables across different condition categories (excluding condition categories with fewer than 700 events in order to be able to fit the models). We selected the final set of risk variables based on the following principles:

i. We excluded risk factors that were statistically significant for very few condition categories, given that they would not contribute much to the overall models.

ii. We excluded risk factors that behaved in clinically incoherent ways. For example, we dropped risk factors that sometimes increased risk and sometimes decreased risk, when we could not identify a clinical rationale for the differences.

iii. We excluded risk factors that were predominantly protective when we felt this protective effect was not clinically reasonable but more likely reflected coding factors. For example, hypertension (CC 91), drug/alcohol abuse without dependence (CC 53) and delirium and encephalopathy (CC 48) were all protective for readmission risk although clinically they should increase patients’ severity of illness. It is possible these factors appeared falsely protective because they were coded more often in healthier patients

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who had few other comorbidities than in sicker patients who had more competing comorbidities to include in the billing form.

iv. Where possible, we grouped together risk factors that were clinically coherent and carried similar risks across condition categories. For example, we combined coronary artery disease (CCs 83-84) with cerebrovascular disease (CCs 98, 99, and 103).

v. We examined risk factors that had been combined in previous CMS publicly reported measures, and in one instance separated them: for cancers, the previous measures generally pool 5 categories of cancers (CCs 8 to12), together. In our analysis, lung cancer (CC 8) and other severe cancers (CC 9) carried higher risks, so we separated them into a distinct risk factor and grouped other major cancers (CC 10), benign cancers (CC 11), and cancers of the urinary and GI tracts (CC 12) together. Consistent with other publicly-reported measures, we also left metastatic cancer/leukemia (CC 7) as a separate risk factor.

The final list containing 74 CMS CCs, grouped into 31 risk variables, is shown in Appendix F.

2.5.3 Service mix adjustment

For all condition categories with sufficient volume (defined as those with more than 1,000 admissions nationally each year), we include a condition-specific indicator in the model.

Rationale: Condition categories differ in their baseline readmission risks and hospitals will differ in their relative distribution of these condition categories within each cohort (service mix). When comparing hospitals it is thus best to compare hospitals with similar service mix. Where this is not feasible, comparison is made more accurate by using an indicator variable for the discharge condition category in addition to risk variables for comorbid conditions.

2.6 Statistical Approach to Model Development

We used a full year of admission data from 2008, with 12 months history data (i.e., 2007), to create the condition cohorts and select risk variables. To assess reliability of the model performance, we combined 2007 and 2008 data, randomly split this dataset and ran the model on each split sample. To assess the stability of the model over time we compared estimates based on 2008 data to estimates based on 2009 data.

2.6.1 Models for each cohort of conditions

Due to the natural clustering of observations within hospitals, we used hierarchical generalized linear models (HGLMs) to model the log-odds of readmission for each

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of the 7 cohorts.39 Readmission within 30 days was modeled as a function of patient-level demographic and clinical characteristics and a random hospital-level intercept. This model specification accounts for within-hospital correlation of the observed outcomes and models the assumption that underlying differences in quality among the health care facilities being evaluated lead to systematic differences in outcomes. We estimated a separate logistic HGLM model for each cohort of condition categories.

We used the results of each HGLM to calculate the predicted number of readmissions and the expected number of readmissions at each hospital. The predicted number of readmissions in each cohort was calculated, using the corresponding HGLM, as the sum of the predicted probability of readmission for each patient, including the hospital-specific (random) effect. The expected number of readmissions in each cohort for each hospital was similarly calculated as the sum of the predicted probability of readmission for each patient, ignoring the hospital specific (random) effect.

Specifically, for a given cohort, we estimate a hierarchical generalized linear model as follows. Let Yij denote the outcome (equal to 1 if patient i is readmitted within 30 days, zero otherwise) for a patient in cohort C ⊆ {1.,,,.7} at hospital j; Zij denotes a set of risk factors. Let M denote the total number of hospitals and mj the number of index patient stays in hospital j. We assume the outcome is related linearly to the covariates via a logit function:

logit(Prob(Yi = 1)) = αj + β*Zij (1)

αj = μ + ωj ; ωj ~ N(0,τ2)

where Zij = (Z1, Z2, ... Zk) is a set of k patient-level covariates. αj represents the

hospital specific intercept; μ is the adjusted average outcome over all hospitals; and τ2 is the between hospital variance component. The HGLM for each cohort was estimated using the SAS software system (GLIMMIX procedure).

Then, to calculate the predicted number of admissions predAj for index admissions in cohort C=1,...,7 at hospital j, we used

predCj = ∑logit -1(αj + β*Zij) (2)

where the sum is over all mCj index admissions in cohort C with index admissions at hospital j. To calculate the expected number expAj we used

expCj = ∑logit-1(μ + β*Zij) (3)

Then, as a measure of excess or reduced readmissions among index admissions in cohort C at hospital j, we calculated the risk-adjusted readmission ratio RCj as

RCj = predCj/expCj (4)

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2.6.2 Hospital performance reporting

The previous section describes how the risk-standardized readmission ratio for each hospital and each cohort is estimated using a separate HGLM for that cohort. To report a single readmission score, the separate risk-standardized readmission ratios were combined into a single value. We created a single score as follows.

For a given hospital, j, which has patients in some subset of cohorts C ⊆ {1,...,7}, calculate the risk-standardized readmission ratio as described above for each condition cohort for which the hospital discharged patients. If the hospital does not have index admissions in a given cohort c, then mcj = 0 and we take Rcj = 1. Then, calculate the volume-weighted logarithmic mean:

Rj = exp( (∑ mcj log(Rcj)) / ∑mcj ) (5)

where the sums are over all condition cohorts; note that if a hospital does not have index admissions in a given cohort (mcj = 0) then that cohort contributes nothing to the overall score Rj. This value, Rj , is the risk-standardized hospital-wide readmission ratio. To improve interpretation, this ratio is then multiplied by the overall national readmission rate for all index admissions in all cohorts, Y, to produce the risk-standardized hospital-wide readmission rate.

RSRRj = Rj (6)

2.6.3 Creating interval estimates

Because the statistic described in Equation (5) is a complex function of parameter estimates, we will use re-sampling and simulation techniques to derive an interval estimate for the final risk-standardized rate. The bootstrapping simulation has the advantage of avoiding unnecessary distributional assumptions.

2.6.4 Algorithm

Let M denote the total number of hospitals in the sample. We repeat steps 1 – 4 below for b = 1,2,…B times:

1. Sample M hospitals with replacement.

2. Fit the seven cohort HGLMs using all patients within each sampled hospital. We use as starting values the parameter estimates obtained by fitting the model to all hospitals. If some hospitals are selected more than once in a bootstrapped sample, we treat them as distinct so that we have M random effects to estimate the variance components. At the conclusion of Step 2, we have:

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a. β(b), the vector of coefficients, and the corresponding variance covariance matrix V.

b. μ(b), the average hospital rate; τ2(b), the between hospital variance, and

c. the set of hospital-specific intercepts and corresponding variances; {αj(b) ,

var[αj(b)] : j = 1,2,…,M}

3. We generate a hospital random effect by sampling from the distribution of the hospital-specific distribution obtained in Step 2c. We approximate the distribution for each random effect by a normal distribution. Thus, we draw αj

(b*) ~ N(αj(b) , var[αj

(b)]) for the unique set of hospitals sampled in Step 1.

4. Within each unique hospital j sampled in Step 1, and using index admissions i=1,...,mj in that hospital, we calculate R*j and then RSRR*j as in equations (5) and (6).

Ninety-five percent interval estimates (or alternative interval estimates) for the hospital-standardized outcome can be computed by identifying the 2.5th and 97.5th percentiles of randomly half of the B estimates (or the percentiles corresponding to the alternative desired intervals).

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3. RESULTS

Figure 3 – Distribution of 30-day hospital-wide readmission rates

Figure 3a –Unadjusted rate

   

Figure 3b –Risk-standardized rate

 

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Table 4 – Frequency of hospitals in each cohort (Number of hospitals = 4919)

Cohort  Frequency  Percent 

Medicine  4860  98.8

Surgical  4272  86.85

Cancer  3784  76.93

Cardiovascular  4633  94.19

Cardiorespiratory  4746  96.48

Psychiatry  4306  87.54

Neurology  4639  94.31

Table 5 – Number of hospitals based on number of models to which they contribute

Total Cohorts 

Frequency  Percent Cumulative Frequency 

Cumulative Percent 

1  64  1.3  64 1.32  122  2.48  186 3.783  102  2.07  288 5.854  157  3.19  445 9.055  337  6.85  782 15.96  646  13.13  1428 29.037  3491  70.97  4919 100

Table 6 – C-statistic for each model Cohort  C‐statistic Medicine 0.640 Surgical 0.676 Cancer 0.604 Cardiovascular 0.654 Cardiorespiratory 0.629 Psych 0.605 Neurology 0.614 

 

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4. SUMMARY

In this draft measure methodology report, we present a measure for 30‐day readmission following hospitalization for any condition that is based on administrative claims data for FFS Medicare beneficiaries 65 years and older. The measure is comprised of seven hierarchical logistic regression models, each of which includes a clinically coherent group of admissions. The measure includes adjustment for case mix (patient comorbidity) and service mix (types of conditions and procedures cared for by the hospital). The measure excludes planned readmissions. Our approach to model development and risk adjustment is consistent with quality measure methods recommendations for publicly‐reported outcomes measures from NQF, CMS, and the American Heart Association scientific statement.

Results to date show that this measure captures 95% of eligible Medicare admissions and 88% of readmissions following those admissions, that most hospitals (71%) have admissions in every cohort, and that c-statistics for performance of each model are consistent with other public report measures. Reliability testing is under way. The measure will also be tested with all-payer data and modified as necessary to apply to the full spectrum of adult hospitalized patients. The measure will be completed in September, at which time we will provide full data on model performance and the final measure methodology.

We now seek public comment on the proposed methods, including inclusion/exclusion criteria, cohort definitions and definition of planned readmissions.

 

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6. APPENDIX – TABLES

Appendix A – Top 10 primary discharge diagnoses for planned procedures

Proc CCS 

Procedure CCS CCS  Diag 

CCS‐ Diagnosis Description  30‐Day 

Readmits   Total 

Admits  Obs 30‐

Day Rate 2  Insertion; 

replacement; or removal of extracranial ventricular shunt 

   Total        1,203   6,697   18.0% 

  81  Other hereditary and degenerative nervous system conditions 

         629   4,205   15.0% 

  237  Complication of device; implant or graft           198      984   20.1%   109  Acute cerebrovascular disease           173       734   23.6%   233  Intracranial injury  45          167   26.9%   42  Secondary malignancies  25         75   33.3%   47  Other and unspecified benign neoplasm  21          71   29.6%   238  Complications of surgical procedures or medical 

care 18             59   30.5% 

  95  Other nervous system disorders  12            77   15.6%   35  Cancer of brain and nervous system    9             43   20.9%   2  Septicemia (except in labor)    8             24   33.3% 3  Laminectomy; 

excision intervertebral disc 

   Total        8,904   103,340   8.6%   205  Spondylosis; intervertebral disc disorders; other 

back problems       6,535     85,978   7.6% 

  209  Other acquired deformities           462       5,354   8.6%   217  Other congenital anomalies           130       1,524   8.5%   237  Complication of device; implant or graft           186    1,308   14.2%   238  Complications of surgical procedures or medical 

care          228       1,157   19.7% 

  231  Other fractures           129        768   16.8%   212  Other bone disease and musculoskeletal 

deformities          109         766   14.2% 

  207  Pathological fracture           125      647   19.3%   81  Other hereditary and degenerative nervous system 

conditions          149        634   23.5% 

  42  Secondary malignancies           131       463   28.3% 10  Thyroidectomy; 

partial or complete 

   Total           802   11,084   7.2%   48  Thyroid disorders           241   5,121   4.7%   36  Cancer of thyroid           292      2,848   10.3%   47  Other and unspecified benign neoplasm  74     1,739   4.3%   51  Other endocrine disorders  31        354   8.8%   11  Cancer of head and neck  25        123   20.3%   42  Secondary malignancies  15        82   18.3%   38  Non‐Hodgkin`s lymphoma  14         66   21.2%   131  Respiratory failure; insufficiency; arrest (adult)  10         56   17.9%   2  Septicemia (except in labor)    7         43   16.3%   101  Coronary atherosclerosis and other heart disease    8        32   25.0% 36  Lobectomy or 

pneumonectomy    Total        3,883    28,904   13.4% 

  19  Cancer of bronchus; lung        2,679    19,827   13.5%   133  Other lower respiratory disease           274   2,793   9.8%   42  Secondary malignancies           216       2,075   10.4%   130  Pleurisy; pneumothorax; pulmonary collapse           154    1,019   15.1%   122  Pneumonia (except that caused by tuberculosis or 

sexually transmitted disease) 94     545   17.2% 

  127  Chronic obstructive pulmonary disease and bronchiectasis 

64      362   17.7% 

  101  Coronary atherosclerosis and other heart disease  36        172   20.9% 

  DRAFT  36  

Proc  CCS    30‐Day   Total  Obs 30‐Procedure CCS  CCS‐ Diagnosis Description 

CCS  Diag  Readmits   Admits   Day Rate 238   Complications of surgical procedures or medical 

care 30      172   17.4% 

  38  Non‐Hodgkin`s lymphoma  21         148   14.2%   4  Mycoses  20      131   15.3% 43  Heart valve 

procedures    Total        9,348   41,913   22.3% 

  96  Heart valve disorders        6,610     30,925   21.4%   101  Coronary atherosclerosis and other heart disease        1,018     4,257   23.9%   100  Acute myocardial infarction           449     1,672   26.9%   108  Congestive heart failure; nonhypertensive           375    1,313   28.6%   237  Complication of device; implant or graft           305   1,260   24.2%   115  Aortic; peripheral; and visceral artery aneurysms           197        813   24.2%   97  Peri‐; endo‐; and myocarditis; cardiomyopathy 

(except that caused by tuberculosis or sexually transm 

         120     460   26.1% 

  213  Cardiac and circulatory congenital anomalies  60       394   15.2%   106  Cardiac dysrhythmias  66     246   26.8%   99  Hypertension with complications and secondary 

hypertension 22           64   34.4% 

44  Coronary artery bypass graft (CABG) 

   Total      17,449   93,852   18.6%   101  Coronary atherosclerosis and other heart disease        9,754   58,416   16.7%   100  Acute myocardial infarction        3,639   17,656   20.6%   96  Heart valve disorders        2,655    11,993   22.1%   237  Complication of device; implant or graft           334       1,717   19.5%   108  Congestive heart failure; nonhypertensive           379      1,247   30.4%   106  Cardiac dysrhythmias           126      505   25.0%   115  Aortic; peripheral; and visceral artery aneurysms           121     469   25.8%   97  Peri‐; endo‐; and myocarditis; cardiomyopathy 

(except that caused by tuberculosis or sexually transm 

49      176   27.8% 

  238  Complications of surgical procedures or medical care 

32       131   24.4% 

  114  Peripheral and visceral atherosclerosis  27       80   33.8% 45  Percutaneous 

transluminal coronary angioplasty (PTCA) 

   Total      36,600   239,412   15.3% 

  101  Coronary atherosclerosis and other heart disease      17,349   133,645   13.0%   100  Acute myocardial infarction      12,841   72,027   17.8%   237  Complication of device; implant or graft        2,382    17,465   13.6%   108  Congestive heart failure; nonhypertensive        1,138       4,091   27.8%   106  Cardiac dysrhythmias           568   2,775   20.5%   131  Respiratory failure; insufficiency; arrest (adult)           216     764   28.3%   2  Septicemia (except in labor)           140         528   26.5%   127  Chronic obstructive pulmonary disease and 

bronchiectasis          148         469   31.6% 

  122  Pneumonia (except that caused by tuberculosis or sexually transmitted disease) 

         131         468   28.0% 

  99  Hypertension with complications and secondary hypertension 

         110   468   23.5% 

48  Insertion; revision; replacement; removal of cardiac pacemaker or cardioverter/ 

   Total      27,971   185,737   15.1% 

  106  Cardiac dysrhythmias      10,102    74,614   13.5%   105  Conduction disorders        3,663     31,993   11.4%   108  Congestive heart failure; nonhypertensive        3,957   21,542   18.4%   237  Complication of device; implant or graft        2,012    14,114   14.3%   101  Coronary atherosclerosis and other heart disease        1,585     11,237   14.1%   100  Acute myocardial infarction        1,270    5,389   23.6% 

  DRAFT  37  

Proc  CCS    30‐Day   Total  Obs 30‐Procedure CCS  CCS‐ Diagnosis Description 

CCS  Diag  Readmits   Admits   Day Rate   defibrillator  97  Peri‐; endo‐; and myocarditis; cardiomyopathy 

(except that caused by tuberculosis or sexually transm 

         381    2,954   12.9% 

  96  Heart valve disorders           609     2,624   23.2%   245  Syncope           287   2,174   13.2%   109  Acute cerebrovascular disease           265    1,466   18.1% 51  Endarterectomy; 

vessel of head and neck 

   Total        6,017   59,461   10.1% 

  110  Occlusion or stenosis of precerebral arteries        4,940   53,549   9.2%   109  Acute cerebrovascular disease           326   2,471   13.2%   101  Coronary atherosclerosis and other heart disease           257    1,212   21.2%   100  Acute myocardial infarction  65       276   23.6%   112  Transient cerebral ischemia  30     201   14.9%   96  Heart valve disorders  54       185   29.2%   106  Cardiac dysrhythmias  32      148   21.6%   114  Peripheral and visceral atherosclerosis  25     111   22.5%   237  Complication of device; implant or graft  15     109   13.8%   108  Congestive heart failure; nonhypertensive  38         90   42.2% 52  Aortic resection; 

replacement or anastomosis 

   Total        3,705   27,182   13.6%   115  Aortic; peripheral; and visceral artery aneurysms        3,345   25,354   13.2%   237  Complication of device; implant or graft           137   893   15.3%   96  Heart valve disorders  36   154   23.4%   114  Peripheral and visceral atherosclerosis  20      103   19.4%   101  Coronary atherosclerosis and other heart disease  23         88   26.1%   238  Complications of surgical procedures or medical 

care 15        44   34.1% 

  100  Acute myocardial infarction  10            39   25.6%   108  Congestive heart failure; nonhypertensive  10         32   31.3%   106  Cardiac dysrhythmias    6           25   24.0%   2  Septicemia (except in labor)    6         23   26.1% 55  Peripheral 

vascular bypass    Total        6,468    29,739   21.7% 

  114  Peripheral and visceral atherosclerosis        2,735    15,179   18.0%   115  Aortic; peripheral; and visceral artery aneurysms           556    3,117   17.8%   248  Gangrene        1,042     3,017   34.5%   237  Complication of device; implant or graft           631     2,647   23.8%   116  Aortic and peripheral arterial embolism or 

thrombosis          415     2,144   19.4% 

  50  Diabetes mellitus with complications           510      1,614   31.6%   117  Other circulatory disease  95       425   22.4%   238  Complications of surgical procedures or medical 

care 81       314   25.8% 

  2  Septicemia (except in labor)  42        125   33.6%   201  Infective arthritis and osteomyelitis (except that 

caused by tuberculosis or sexually transmitted di 28       86   32.6% 

60  Embolectomy and endarterectomy of lower limbs 

   Total        4,229    18,918   22.4%   114  Peripheral and visceral atherosclerosis        1,447   7,997   18.1%   116  Aortic and peripheral arterial embolism or 

thrombosis          796    3,349   23.8% 

  237  Complication of device; implant or graft           448     1,854   24.2%   115  Aortic; peripheral; and visceral artery aneurysms           333     1,848   18.0%   248  Gangrene           422   1,182   35.7%   50  Diabetes mellitus with complications           167   522   32.0%   238  Complications of surgical procedures or medical 

care 82       405   20.2% 

  117  Other circulatory disease  42      200   21.0%   101  Coronary atherosclerosis and other heart disease  53     198   26.8% 

  DRAFT  38  

Proc  CCS    30‐Day   Total  Obs 30‐Procedure CCS  CCS‐ Diagnosis Description 

CCS  Diag  Readmits   Admits   Day Rate 100   Acute myocardial infarction  54       182   29.7% 

64  Bone marrow transplant 

   Total           268   1,102   24.3%   40  Multiple myeloma  83   466   17.8%   38  Non‐Hodgkin`s lymphoma  85   316   26.9%   39  Leukemias  58   168   34.5%   45  Maintenance chemotherapy; radiotherapy  12   37   32.4%   37  Hodgkin`s disease    4   28   14.3%   44  Neoplasms of unspecified nature or uncertain 

behavior 13   25   52.0% 

  58  Other nutritional; endocrine; and metabolic disorders 

  4   18   22.2% 

  237  Complication of device; implant or graft    2        7   28.6%   250  Nausea and vomiting    2             2   100.0%   106  Cardiac dysrhythmias    1           2   50.0% 74  Gastrectomy; 

partial and total    Total        1,294      6,355   20.4% 

  13  Cancer of stomach           590   2,925   20.2%   12  Cancer of esophagus  93       430   21.6%   139  Gastroduodenal ulcer (except hemorrhage)  91    413   22.0%   153  Gastrointestinal hemorrhage  89      338   26.3%   44  Neoplasms of unspecified nature or uncertain 

behavior 25      337   7.4% 

  141  Other disorders of stomach and duodenum  62         296   20.9%   47  Other and unspecified benign neoplasm  42   280   15.0%   238  Complications of surgical procedures or medical 

care 37      142   26.1% 

  17  Cancer of pancreas  34        135   25.2%   143  Abdominal hernia  24    112   21.4% 75  Small bowel 

resection    Total        4,697    24,425   19.2% 

  145  Intestinal obstruction without hernia        1,212    6,861   17.7%   143  Abdominal hernia           635     3,722   17.1%   155  Other gastrointestinal disorders           404       2,074   19.5%   114  Peripheral and visceral atherosclerosis           327       1,459   22.4%   14  Cancer of colon           228     1,195   19.1%   42  Secondary malignancies           256    1,040   24.6%   146  Diverticulosis and diverticulitis           161   1,038   15.5%   238  Complications of surgical procedures or medical 

care          187        829   22.6% 

  2  Septicemia (except in labor)           178      635   28.0%   237  Complication of device; implant or graft           141          603   23.4% 78  Colorectal 

resection    Total      16,436   102,473   16.0% 

  14  Cancer of colon        5,035   36,222   13.9%   146  Diverticulosis and diverticulitis        2,230    15,600   14.3%   47  Other and unspecified benign neoplasm        1,075   10,139   10.6%   15  Cancer of rectum and anus        1,691    9,298   18.2%   145  Intestinal obstruction without hernia           943    4,634   20.4%   155  Other gastrointestinal disorders           862    4,629   18.6%   147  Anal and rectal conditions           313   2,374   13.2%   114  Peripheral and visceral atherosclerosis         570   2,249   25.3% 

  2  Septicemia (except in labor)           500     1,912   26.2%   238  Complications of surgical procedures or medical 

care          326   1,677   19.4% 

80  Appendectomy     Total        2,894     24,117   12.0%   142  Appendicitis and other appendiceal conditions        1,285    14,041   9.2%   145  Intestinal obstruction without hernia           155    1,145   13.5% 

  DRAFT  39  

Proc CCS 

Procedure CCS CCS  Diag 

 30‐Day Readmits  

 Total Admits  

Obs 30‐CCS‐ Diagnosis Description 

Day Rate   14  Cancer of colon           159      1,113   14.3%   146  Diverticulosis and diverticulitis           133    1,016   13.1%   27  Cancer of ovary           122   694   17.6%   47  Other and unspecified benign neoplasm  69     667   10.3%   155  Other gastrointestinal disorders  96    592   16.2%   2  Septicemia (except in labor)           104   520   20.0%   32  Cancer of bladder           136    511   26.6%   15  Cancer of rectum and anus  83     484   17.1% 84  Cholecystectomy 

and common duct exploration 

   Total      12,476   95,087  13.1%   149  Biliary tract disease        7,825    67,494   11.6%   152           861     7,090   12.1% Pancreatic disorders (not diabetes) 

2   Septicemia (except in labor)           633    3,590   17.6%   14  Cancer of colon           259   1,876   13.8%   17  Cancer of pancreas           326    1,436   22.7%   18  Cancer of other GI organs; peritoneum           252     1,124   22.4%   42  Secondary malignancies           140   915   15.3%   145  Intestinal obstruction without hernia           134      843   15.9%   143  Abdominal hernia           122    762   16.0%   47  Other and unspecified benign neoplasm           133        722   18.4% 85  Inguinal and 

femoral hernia repair 

   Total        2,193    17,933   12.2%   143  Abdominal hernia        1,588     13,922   11.4%   238  Complications of surgical procedures or medical 

care 53      399   13.3% 

  29  Cancer of prostate  21      388   5.4%   145  Intestinal obstruction without hernia  57     290   19.7%   14  Cancer of colon  23       183   12.6%   149  Biliary tract disease  22        174   12.6%   2  Septicemia (except in labor)  31   124   25.0%   237  Complication of device; implant or graft  20   100   20.0%   114  Peripheral and visceral atherosclerosis      21     91   23.1%   32  Cancer of bladder  26   84   31.0% 103  Nephrotomy and 

nephrostomy    Total        3,089   11,493   26.9% 

  160  Calculus of urinary tract           491   2,989   16.4%   2  Septicemia (except in labor)           421    1,474   28.6%   157  Acute and unspecified renal failure           438       1,363   32.1%   161  Other diseases of kidney and ureters           270      1,068   25.3%   32  Cancer of bladder           301      900   33.4%   159  Urinary tract infections           168       545   30.8%   237  Complication of device; implant or graft           127       412   30.8%   42  Secondary malignancies           118        404   29.2%   238  Complications of surgical procedures or medical 

care          108      380   28.4% 

  29  Cancer of prostate  60        216   27.8% 104  Nephrectomy; 

partial or complete 

   Total        1,766   16,132   10.9%   33  Cancer of kidney and renal pelvis        1,130   11,079   10.2%   161  Other diseases of kidney and ureters  98       1,097   8.9%   47  Other and unspecified benign neoplasm  77     1,060   7.3%   34  Cancer of other urinary organs  91    826   11.0%   32  Cancer of bladder  45         208   21.6%   159  Urinary tract infections  34      179   19.0%   42  Secondary malignancies  22      158   13.9%   215  Genitourinary congenital anomalies  19        136   14.0%   99  Hypertension with complications and secondary 

hypertension 24       127   18.9% 

  237  Complication of device; implant or graft  26     88   29.5% 105  Kidney    Total  551  1,811  30.4% 

  DRAFT  40  

Proc CCS 

Procedure CCS CCS  Diag 

 30‐Day Readmits  

 Total Admits  

Obs 30‐CCS‐ Diagnosis Description 

Day Rate   transplant  99  Hypertension with complications and secondary 

hypertension          316   1,038   30.4% 

  50  Diabetes mellitus with complications           144      445   32.4%   158  Chronic renal failure  58   200   29.0%   237  Complication of device; implant or graft  14         49   28.6%   215  Genitourinary congenital anomalies    7           23   30.4%   156  Nephritis; nephrosis; renal sclerosis    6        19   31.6%   151  Other liver diseases    2        8   25.0%   115  Aortic; peripheral; and visceral artery aneurysms    1          6   16.7%   117  Other circulatory disease    1         4   25.0%   157  Acute and unspecified renal failure    1         3   33.3% 113  Transurethral 

resection of prostate (TURP) 

   Total        4,237    41,835   10.1%   164  Hyperplasia of prostate        2,319    28,747   8.1%   29  Cancer of prostate           440    4,073   10.8%   32  Cancer of bladder           175       1,362   12.8%   162  Other diseases of bladder and urethra  93   1,065   8.7%   160  Calculus of urinary tract  69     846   8.2%   163  Genitourinary symptoms and ill‐defined conditions           131      797   16.4%   159  Urinary tract infections           127       583   21.8%   238  Complications of surgical procedures or medical 

care 72   548   13.1% 

  157  Acute and unspecified renal failure           110   507   21.7%   2  Septicemia (except in labor)  95   362   26.2% 114  Open 

prostatectomy    Total        1,010   20,783   4.9% 

  29  Cancer of prostate           771   18,482   4.2%   164  Hyperplasia of prostate           137   1,763   7.8%   32  Cancer of bladder  35   165   21.2%   162  Other diseases of bladder and urethra    4   36   11.1%   238  Complications of surgical procedures or medical 

care   5   31   16.1% 

  160  Calculus of urinary tract    5   29   17.2%   165  Inflammatory conditions of male genital organs    6   23   26.1%   163  Genitourinary symptoms and ill‐defined conditions    4   18   22.2%   166  Other male genital disorders    4   18   22.2%   15  Cancer of rectum and anus    4   15   26.7% 119  Oophorectomy; 

unilateral and bilateral 

   Total        3,530   35,902   9.8%   25  Cancer of uterus           940   9,228   10.2%   170  Prolapse of female genital organs           218   5,648   3.9%   47  Other and unspecified benign neoplasm           302   4,165   7.3%   27  Cancer of ovary           697   3,766   18.5%   175  Other female genital disorders           117   2,009   5.8%   172  Ovarian cyst  99   1,574   6.3%   14  Cancer of colon           131   976   13.4%   146  Diverticulosis and diverticulitis  92   659   14.0%   18  Cancer of other GI organs; peritoneum           106   495   21.4%   42  Secondary malignancies           102   491   20.8% 124  Hysterectomy; 

abdominal and vaginal 

   Total        2,732   35,432   7.7%   170  Prolapse of female genital organs           430   12,633   3.4%   25  Cancer of uterus           965   9,479   10.2%   27  Cancer of ovary           427   2,429   17.6%   47  Other and unspecified benign neoplasm           137   2,008   6.8%   175  Other female genital disorders  97   1,960   4.9%   46  Benign neoplasm of uterus  86   1,660   5.2%   26  Cancer of cervix  61   699   8.7%   18  Cancer of other GI organs; peritoneum  67   319   21.0% 

  DRAFT  41  

Proc CCS 

Procedure CCS CCS  Diag 

 30‐Day Readmits  

 Total Admits  

Obs 30‐CCS‐ Diagnosis Description 

Day Rate 42   Secondary malignancies  52   274   19.0% 

  32  Cancer of bladder  56   195   28.7% 145  Treatment; 

fracture or dislocation of radius and ulna 

   Total        2,048   18,197   11.3%   229  Fracture of upper limb        1,146   12,208   9.4%   226  Fracture of neck of femur (hip)           369   2,325   15.9%   230  Fracture of lower limb  51   435   11.7%   231  Other fractures  49   373   13.1%   233  Intracranial injury  68   367   18.5%   237  Complication of device; implant or graft  43   326   13.2%   212  Other bone disease and musculoskeletal 

deformities 19   206   9.2% 

  245  Syncope  29   191   15.2%   106  Cardiac dysrhythmias  22   119   18.5%   238  Complications of surgical procedures or medical 

care 19   98   19.4% 

147  Treatment; fracture or dislocation of lower extremity (other than hip or femur) 

   Total        4,361   34,131   12.8%   230  Fracture of lower limb        3,223   26,133   12.3%   237  Complication of device; implant or graft           345   2,302   15.0%   203  Osteoarthritis  67   953   7.0%   212  Other bone disease and musculoskeletal 

deformities 76   766   9.9% 

  238  Complications of surgical procedures or medical care 

70   426   16.4% 

  225  Joint disorders and dislocations; trauma‐related  41   351   11.7%   229  Fracture of upper limb  32   279   11.5%   207  Pathological fracture  50   277   18.1%   226  Fracture of neck of femur (hip)  30   231   13.0%   233  Intracranial injury  26   136   19.1% 148  Other fracture 

and dislocation procedure 

   Total        4,064   31,991   12.7%   229  Fracture of upper limb        1,421   12,285   11.6%   205  Spondylosis; intervertebral disc disorders; other 

back problems          448   4,687   9.6% 

  237  Complication of device; implant or graft           503   3,957   12.7%   231  Other fractures           194   1,252   15.5%   225  Joint disorders and dislocations; trauma‐related           152   1,237   12.3%   212  Other bone disease and musculoskeletal 

deformities          127   1,222   10.4% 

  226  Fracture of neck of femur (hip)           207   1,154   17.9%   207  Pathological fracture           166   809   20.5%   230  Fracture of lower limb  91   470   19.4%   238  Complications of surgical procedures or medical 

care 77   450   17.1% 

152  Arthroplasty knee 

   Total      15,063   250,228   6.0%   203  Osteoarthritis      12,785   226,600   5.6%   237  Complication of device; implant or graft        1,588   16,662   9.5%   204  Other non‐traumatic joint disorders  94   1,749   5.4%   209  Other acquired deformities           141   1,171   12.0%   202  Rheumatoid arthritis and related disease  71   982   7.2%   225  Joint disorders and dislocations; trauma‐related  54   666   8.1%   212  Other bone disease and musculoskeletal 

deformities 42   603   7.0% 

  230  Fracture of lower limb  91   534   17.0%   238  Complications of surgical procedures or medical 

care 37   230   16.1% 

  DRAFT  42  

Proc CCS 

Procedure CCS CCS  Diag 

 30‐Day Readmits  

 Total Admits  

Obs 30‐CCS‐ Diagnosis Description 

Day Rate 201   Infective arthritis and osteomyelitis (except that 

caused by tuberculosis or sexually transmitted di 31   180   17.2% 

153  Hip replacement; total and partial 

   Total      20,643   184,630   11.2%   203  Osteoarthritis        5,349   86,059   6.2%   226  Fracture of neck of femur (hip)      10,996   68,890   16.0%   237  Complication of device; implant or graft        2,601   18,074   14.4%   212  Other bone disease and musculoskeletal 

deformities          568   5,086   11.2% 

  207  Pathological fracture           308   1,838   16.8%   204  Other non‐traumatic joint disorders  57   607   9.4%   209  Other acquired deformities  62   440   14.1%   230  Fracture of lower limb  50   285   17.5%   229  Fracture of upper limb  39   255   15.3%   231  Other fractures  51   217   23.5% 154  Arthroplasty 

other than hip or knee 

   Total        1,669   30,007   5.6%   203  Osteoarthritis           622   15,818   3.9%   229  Fracture of upper limb           406   4,817   8.4%   211  Other connective tissue disease           103   2,093   4.9%   237  Complication of device; implant or graft           153   1,983   7.7%   204  Other non‐traumatic joint disorders  75   1,491   5.0%   212  Other bone disease and musculoskeletal 

deformities 79   914   8.6% 

  232  Sprains and strains  35   792   4.4%   225  Joint disorders and dislocations; trauma‐related  34   541   6.3%   202  Rheumatoid arthritis and related disease  16   381   4.2%   230  Fracture of lower limb  29   232   12.5% 157  Amputation of 

lower extremity    Total      10,822   39,698   27.3% 

  50  Diabetes mellitus with complications        3,243   12,591   25.8%   248  Gangrene        3,065   10,053   30.5%   201  Infective arthritis and osteomyelitis (except that 

caused by tuberculosis or sexually transmitted di          515   2,938   17.5% 

  114  Peripheral and visceral atherosclerosis           810   2,937   27.6%   2  Septicemia (except in labor)           621   2,056   30.2%   238  Complications of surgical procedures or medical 

care          554   2,052   27.0% 

  237  Complication of device; implant or graft           462   1,581   29.2%   199  Chronic ulcer of skin           177   749   23.6%   116  Aortic and peripheral arterial embolism or 

thrombosis          216   642   33.6% 

  117  Other circulatory disease           132   387   34.1% 158  Spinal fusion     Total        7,495   74,484   10.1%   205  Spondylosis; intervertebral disc disorders; other 

back problems       4,782   52,912   9.0% 

  209  Other acquired deformities           853   8,999   9.5%   217  Other congenital anomalies           224   2,710   8.3%   237  Complication of device; implant or graft           303   2,413   12.6%   231  Other fractures           344   2,086   16.5%   212  Other bone disease and musculoskeletal 

deformities          206   1,573   13.1% 

  207  Pathological fracture           201   919   21.9%   227  Spinal cord injury           128   660   19.4%   42  Secondary malignancies           136   536   25.4%   201  Infective arthritis and osteomyelitis (except that 

caused by tuberculosis or sexually transmitted diseases) 

56   252   22.2% 

  DRAFT  43  

  DRAFT  44  

Proc CCS 

Procedure CCS CCS  Diag 

CCS‐ Diagnosis Description  30‐Day 

Readmits   Total 

Admits  Obs 30‐

Day Rate 166  Lumpectomy; 

quadrantectomy of breast 

   Total           483   4,422   10.9%   24  Cancer of breast           278   3,199   8.7%   167  Nonmalignant breast conditions  31   207   15.0%   238  Complications of surgical procedures or medical 

care 18   181   9.9% 

  42  Secondary malignancies  12   61   19.7%   106  Cardiac dysrhythmias  10   38   26.3%   108  Congestive heart failure; nonhypertensive    7   26   26.9%   2  Septicemia (except in labor)    9   18   50.0%   122  Pneumonia (except that caused by tuberculosis or 

sexually transmitted disease)   6   17   35.3% 

  127  Chronic obstructive pulmonary disease and bronchiectasis 

  5   17   29.4% 

  131  Respiratory failure; insufficiency; arrest (adult)    6   11   54.5% 167  Mastectomy     Total        1,265   19,789   6.4%   24  Cancer of breast        1,154   18,854   6.1%   167  Nonmalignant breast conditions  10   178   5.6%   259  Residual codes; unclassified    6   113   5.3%   238  Complications of surgical procedures or medical 

care 10   97   10.3% 

  42  Secondary malignancies  11   73   15.1%   106  Cardiac dysrhythmias    4   20   20.0%   55  Fluid and electrolyte disorders    4   18   22.2%   157  Acute and unspecified renal failure    4   7   57.1%   109  Acute cerebrovascular disease    4   6   66.7%   103  Pulmonary heart disease    3   5   60.0% 176  Other organ 

transplantation    Total           232   677   34.3% 

  151  Other liver diseases  62   184   33.7%   133  Other lower respiratory disease  35   101   34.7%   108  Congestive heart failure; nonhypertensive  18   76   23.7%   16  Cancer of liver and intrahepatic bile duct  16   64   25.0%   127  Chronic obstructive pulmonary disease and 

bronchiectasis 31   56   55.4% 

  663  Screening and history of mental health and substance abuse codes 

19   48   39.6% 

  6  Hepatitis    9   28   32.1%   101  Coronary atherosclerosis and other heart disease    8   28   28.6%   237  Complication of device; implant or graft    5   17   29.4%   149  Biliary tract disease    7   9   77.8% 211  Therapeutic 

radiology for cancer treatment 

   Total        7,089   22,957   30.9%   42  Secondary malignancies        1,572   5,271   29.8%   19  Cancer of bronchus; lung           798   2,662   30.0%   45  Maintenance chemotherapy; radiotherapy           743   1,456   51.0%   29  Cancer of prostate           171   877   19.5%   55  Fluid and electrolyte disorders           225   631   35.7%   122  Pneumonia (except that caused by tuberculosis or 

sexually transmitted disease)          200   598   33.4% 

  38  Non‐Hodgkin`s lymphoma           175   496   35.3%   95  Other nervous system disorders           145   453   32.0%   40  Multiple myeloma           144   407   35.4%   2  Septicemia (except in labor)           143   387   37.0% 

 

Appendix B – List of AHRQ procedure CCs defining the surgical/gynecological cohort

CC  Procedure Maximum Admissions* 

Maximum Readmissions* 

Readmission Rate 

1  Incision and excision of CNS  28,261  5,753  20.40% 

2 Insertion; replacement; or removal of extracranial ventricular shunt 

7,270  1,304  17.90% 

3  Laminectomy; excision intervertebral disc  79,631  6,619  8.30% 

9  Other OR therapeutic nervous system procedures  16,275  2,817  17.30% 

10  Thyroidectomy; partial or complete  12,989  862  6.60% 

12  Other therapeutic endocrine procedures  10,415  1,340  12.90% 

13  Corneal transplant  157  16  10.20% 

14  Glaucoma procedures  130  18  13.80% 

15  Lens and cataract procedures  633  97  15.30% 

16  Repair of retinal tear; detachment  292  33  11.30% 

17  Destruction of lesion of retina and choroid  127  9  7.10% 

20  Other intraocular therapeutic procedures  1,107  138  12.50% 

21 Other extraocular muscle and orbit therapeutic procedures 

1,163  150  12.90% 

22  Tympanoplasty  140  14  10.00% 

23  Myringotomy  450  99  22.00% 

24  Mastoidectomy  273  29  10.60% 

26  Other therapeutic ear procedures  2,002  263  13.10% 

28  Plastic procedures on nose  1,790  213  11.90% 

30  Tonsillectomy and/or adenoidectomy  333  43  12.90% 

33 Other OR therapeutic procedures on nose; mouth and pharynx 

8,040  913  11.40% 

36  Lobectomy or pneumonectomy  32,065  4,350  13.60% 

42 Other OR Rx procedures on respiratory system and mediastinum 

16,452  3,453  21.00% 

43  Heart valve procedures  45,477  10,398  22.90% 

44  Coronary artery bypass graft (CABG)  82,527  14,548  17.60% 

49  Other OR heart procedures  41,585  8,125  19.50% 

51  Endarterectomy; vessel of head and neck  63,024  6,288  10.00% 

52  Aortic resection; replacement or anastomosis  27,967  3,765  13.50% 

53  'Varicose vein stripping; lower limb  245  33  13.50% 

55  Peripheral vascular bypass  28,972  6,163  21.30% 

56  Other vascular bypass and shunt; not heart  2,387  763  32.00% 

59  Other OR procedures on vessels of head and neck  14,335  1,771  12.40% 

60  Embolectomy and endarterectomy of lower limbs  9,770  2,292  23.50% 

61 Other OR procedures on vessels other than head and neck 

178,209  37,411  21.00% 

66  Procedures on spleen  2,903  548  18.90% 

67  Other therapeutic procedures; hemic and lymphatic  42,288  5,557  13.10% 

  DRAFT  45  

Maximum  Maximum  Readmission CC  Procedure 

Admissions*  Readmissions*  Rate system 

72  Colostomy; temporary and permanent  10,365  1,970  19.00% 

73  Ileostomy and other enterostomy  5,592                  1,805   32.3% 74  Gastrectomy; partial and total  6,507  1,305  20.10% 

75  Small bowel resection  21,833  4,255  19.50% 

78  Colorectal resection  105,467  16,702  15.80% 

79 Local excision of large intestine lesion (not endoscopic) 

368  50  13.60% 

80  Appendectomy  19,326  1,851  9.60% 

84  Cholecystectomy and common duct exploration  102,698  13,143  12.80% 

85  Inguinal and femoral hernia repair  14,656  1,683  11.50% 

86  Other hernia repair  33,253  3,887  11.70% 

89  Exploratory laparotomy  2,981  611  20.50% 

90  Excision; lysis peritoneal adhesions  36,415  6,278  17.20% 

94  Other OR upper GI therapeutic procedures  31,731  4,334  13.70% 

96  Other OR lower GI therapeutic procedures  33,387  5,846  17.50% 

99  Other OR gastrointestinal therapeutic procedures  29,873  6,478  21.70% 

101 Transurethral excision; drainage; or removal urinary obstruction 

33225  6075  18.28% 

103  Nephrotomy and nephrostomy  13,530  3,649  27.00% 

104  Nephrectomy; partial or complete  19,504  2,338  12.00% 

105  Kidney transplant  10,873  3,175  29.20% 

106  Genitourinary incontinence procedures  8,819  351  4.00% 

112  Other OR therapeutic procedures of urinary tract  17,650  3,688  20.90% 

113  Transurethral resection of prostate (TURP)  42,523  4,259  10.00% 

114  Open prostatectomy  23,965  1,158  4.80% 

118  Other OR therapeutic procedures; male genital  6,005  835  13.90% 

142  Partial excision bone  37,930  5,070  13.40% 

143  Bunionectomy or repair of toe deformities  931  84  9.00% 

144  Treatment; facial fracture or dislocation  1,968  204  10.40% 

145  Treatment; fracture or dislocation of radius and ulna  14,471  1,466  10.10% 

146  Treatment; fracture or dislocation of hip and femur  149,336  22,795  15.30% 

147 Treatment; fracture or dislocation of lower extremity (other than hip or femur) 

39,901  5,000  12.50% 

148  Other fracture and dislocation procedure  23,019  2,900  12.60% 

150  Division of joint capsule; ligament or cartilage  3,002  230  7.70% 

151  Excision of semilunar cartilage of knee  1,381  181  13.10% 

152  Arthroplasty knee  292,149  17,995  6.20% 

153  Hip replacement; total and partial  207,011  23,096  11.20% 

154  Arthroplasty other than hip or knee  32,597  1,772  5.40% 

157  Amputation of lower extremity  51,213  13,548  26.50% 

  DRAFT  46  

  DRAFT  47  

CC  Procedure Maximum Admissions* 

Maximum Readmissions* 

Readmission Rate 

158  Spinal fusion  106,703  10,307  9.70% 

160 Other therapeutic procedures on muscles and tendons 

32,254  4,998  15.50% 

161  Other OR therapeutic procedures on bone  29,314  5,611  19.10% 

162  Other OR therapeutic procedures on joints  25,661  4,125  16.10% 

164 Other OR therapeutic procedures on musculoskeletal system 

5,963  1,346  22.60% 

166  Lumpectomy; quadrantectomy of breast  2,994  311  10.40% 

167  Mastectomy  16,333  1,102  6.70% 

172  Skin graft  13,987  2,508  17.90% 

175  Other OR therapeutic procedures on skin and breast  6,626  879  13.30% 

176  Other organ transplantation  2,483  855  34.40% 119  Oophorectomy; unilateral and bilateral 33,667 2,856  8.50%

120  Other operations on ovary  906  111  12.30% 

121  Ligation or occlusion of fallopian tubes  228  13  5.70% 

122  Removal of ectopic pregnancy  143  6  4.20% 

123  Other operations on fallopian tubes  937  82  8.80% 

124  Hysterectomy; abdominal and vaginal  48,236  3,515  7.30% 

125  Other excision of cervix and uterus  1,062  131  12.30% 

126  Abortion (termination of pregnancy)  39  10  25.60% 

127 Dilatation and curettage (D&C); aspiration after delivery or abortion  298  26  8.70% 

129 Repair of cystocele and rectocele; obliteration of vaginal vault  14,446  476  3.30% 

131 Other non‐OR therapeutic procedures; female organs  509  115  22.60% 

132  Other OR therapeutic procedures; female organs  13,796  996  7.20% 

133  Episiotomy  372  7  1.90% 

134  Cesarean section  6,226  280  4.50% 

135  Forceps; vacuum; and breech delivery  535  15  2.80% 

136  Artificial rupture of membranes to assist delivery  1,510  37  2.50% 

137  Other procedures to assist delivery  5,131  162  3.20% 

139  Fetal monitoring  1,488 179  12.00%

140  Repair of current obstetric laceration 1,387 38  2.70%

141  Other therapeutic obstetrical procedures 166 10  6.00%

174  Female infertility  1 ‐  0.00%

Total 2008 admissions: 8,203,390

Total 2008 unique readmissions: 1,473,914 *Full Medicare data including those <65 years.  Not mutually exclusive; multiple procedures may be performed during a single admission. 

Appendix C – Condition categories assigned to the medical cohorts

CCS Description Admits Unplanned

30 Day Readmits

Model Group Unplanned

30-Day Readmit

Rate Cardiovascular 106 315,298 50,117 15.9% Cardiac dysrhythmias Cardiovascular 102 Nonspecific chest pain 142,883 15,522 10.9% Cardiovascular 100 Acute myocardial infarction 116,810 25,221 21.6% Cardiovascular 101 Coronary atherosclerosis and other heart disease 116,147 15,240 13.1% Cardiovascular 117 Other circulatory disease 56,016 9,199 16.4% Cardiovascular 105 Conduction disorders 33,899 3,783 11.2% Cardiovascular 114 Peripheral and visceral atherosclerosis 27,169 4,294 15.8%

Cardiovascular 97 Peri-; endo-; and myocarditis; cardiomyopathy (except caused by TB/STD 13,241 2,756 20.8%

Cardiovascular 96 Heart valve disorders 9,920 1,812 18.3% Cardiovascular 115 Aortic; peripheral; and visceral artery aneurysms 5,010 773 15.4%

Cardiovascular 116 Aortic and peripheral arterial embolism or thrombosis 2,570 446 17.4%

Cardiovascular 107 Cardiac arrest and ventricular fibrillation 2,009 362 18.0% Cardiovascular 104 Other and ill-defined heart disease 1,749 253 14.5% Cardiovascular 213 Cardiac and circulatory congenital anomalies 652 118 18.1%

Cardiovascular Total 843,373 129,896 15.4%

Cancer 45 Maintenance chemotherapy; radiotherapy 21,522 4,842 22.5%

Cancer 44 Neoplasms of unspecified nature or uncertain behavior 10,160 3,170 31.2%

Cancer 38 Non-Hodgkin`s lymphoma 7,977 2,373 29.7% Cancer 39 Leukemias 7,809 2,301 29.5% Cancer 40 Multiple myeloma 4,624 1,380 29.8% Cancer 35 Cancer of brain and nervous system 3,561 836 23.5% Cancer 13 Cancer of stomach 3,467 820 23.7% Cancer 29 Cancer of prostate 3,100 497 16.0% Cancer 15 Cancer of rectum and anus 3,030 505 16.7% Cancer 18 Cancer of other GI organs; peritoneum 2,974 792 26.6% Cancer 12 Cancer of esophagus 2,533 604 23.8% Cancer 11 Cancer of head and neck 2,515 681 27.1% Cancer 33 Cancer of kidney and renal pelvis 1,863 397 21.3% Cancer 32 Cancer of bladder 1,807 469 26.0% Cancer 25 Cancer of uterus 1,132 196 17.3% Cancer 36 Cancer of thyroid 879 76 8.6% Cancer 21 Cancer of bone and connective tissue 763 181 23.7% Cancer 20 Cancer; other respiratory and intrathoracic 632 108 17.1% Cancer 23 Other non-epithelial cancer of skin 593 117 19.7% Cancer 26 Cancer of cervix 586 88 15.0% Cancer 28 Cancer of other female genital organs 326 57 17.5% Cancer 34 Cancer of other urinary organs 301 54 17.9% Cancer 37 Hodgkin`s disease 236 72 30.5% Cancer 30 Cancer of testis 4 - 0.0%

Cancer Total 82,394 20,616 25.0%

  DRAFT  48  

Unplanned 30-Day

Readmit Rate

Unplanned 30 Day

Readmits Model Group CCS Description Admits

Cardiorespiratory 108 Congestive heart failure; nonhypertensive 453,342 112,291 24.8% Cardiorespiratory 122 Pneumonia (except that caused by TB/STD) 403,973 71,911 17.8%

Cardiorespiratory 127 Chronic obstructive pulmonary disease and bronchiectasis 297,736 64,450 21.6%

Cardiorespiratory 131 Respiratory failure; insufficiency; arrest (adult) 117,569 28,678 24.4% Cardiorespiratory 128 Asthma 61,696 11,148 18.1% Cardiorespiratory 103 Pulmonary heart disease 45,122 7,496 16.6% Cardiorespiratory 125 Acute bronchitis 25,833 3,301 12.8% Cardiorespiratory Total 1,405,271 299,275 21.3% Medicine 2 Septicemia (except in labor) 236,993 50,800 21.4% Medicine 159 Urinary tract infections 232,590 41,833 18.0% Medicine 55 Fluid and electrolyte disorders 178,808 33,032 18.5% Medicine 157 Acute and unspecified renal failure 163,357 36,435 22.3% Medicine 153 Gastrointestinal hemorrhage 135,891 23,065 17.0% Medicine 197 Skin and subcutaneous tissue infections 111,670 17,171 15.4% Medicine 245 Syncope 107,933 11,885 11.0% Medicine 129 Aspiration pneumonitis; food/vomitus 88,296 19,365 21.9% Medicine 145 Intestinal obstruction without hernia 88,193 14,840 16.8% Medicine 146 Diverticulosis and diverticulitis 85,920 11,991 14.0% Medicine 237 Complication of device; implant or graft 81,549 18,932 23.2%

Medicine 238 Complications of surgical procedures or medical care 81,398 14,994 18.4%

Medicine 59 Deficiency and other anemia 79,517 17,810 22.4% Medicine 50 Diabetes mellitus with complications 74,976 14,418 19.2% Medicine 135 Intestinal infection 70,077 16,274 23.2% Medicine 231 Other fractures 69,105 10,273 14.9%

Medicine 99 Hypertension with complications and secondary hypertension 67,337 14,943 22.2%

Medicine 118 Phlebitis; thrombophlebitis and thromboembolism 48,254 7,098 14.7%

Medicine 205 Spondylosis; intervertebral disc disorders; other back problems 46,916 7,457 15.9%

Medicine 155 Other gastrointestinal disorders 44,151 9,008 20.4% Medicine 133 Other lower respiratory disease 36,203 6,484 17.9% Medicine 152 Pancreatic disorders (not diabetes) 34,779 5,541 15.9% Medicine 149 Biliary tract disease 33,718 5,583 16.6% Medicine 138 Esophageal disorders 33,354 4,778 14.3% Medicine 154 Noninfectious gastroenteritis 33,236 4,775 14.4% Medicine 259 Residual codes; unclassified 32,960 5,931 18.0% Medicine 93 Conditions associated with dizziness or vertigo 30,934 2,358 7.6% Medicine 130 Pleurisy; pneumothorax; pulmonary collapse 29,482 7,543 25.6% Medicine 140 Gastritis and duodenitis 29,329 5,002 17.1% Medicine 211 Other connective tissue disease 28,565 4,163 14.6% Medicine 251 Abdominal pain 27,091 4,480 16.5% Medicine 151 Other liver diseases 20,612 6,340 30.8%

Medicine 244 Other injuries and conditions due to external causes 20,470 3,104 15.2%

Medicine 98 Essential hypertension 18,409 2,142 11.6%

  DRAFT  49  

Unplanned 30-Day

Readmit Rate

Unplanned 30 Day

Readmits Model Group CCS Description Admits

Medicine 207 Pathological fracture 18,040 3,823 21.2% Medicine 239 Superficial injury; contusion 17,651 2,710 15.4% Medicine 141 Other disorders of stomach and duodenum 17,168 3,616 21.1%

Medicine 58 Other nutritional; endocrine; and metabolic disorders 16,379 3,416 20.9%

Medicine 199 Chronic ulcer of skin 16,350 3,425 20.9% Medicine 51 Other endocrine disorders 16,343 3,200 19.6% Medicine 229 Fracture of upper limb 15,309 2,506 16.4% Medicine 252 Malaise and fatigue 14,677 2,443 16.6% Medicine 63 Diseases of white blood cells 14,138 3,399 24.0% Medicine 123 Influenza 14,096 1,689 12.0% Medicine 7 Viral infection 13,805 2,200 15.9% Medicine 230 Fracture of lower limb 13,448 2,049 15.2% Medicine 246 Fever of unknown origin 13,079 2,323 17.8% Medicine 242 Poisoning by other medications and drugs 12,394 1,934 15.6% Medicine 160 Calculus of urinary tract 12,195 1,573 12.9% Medicine 163 Genitourinary symptoms and ill-defined conditions 11,122 1,948 17.5% Medicine 204 Other non-traumatic joint disorders 10,891 1,567 14.4% Medicine 250 Nausea and vomiting 10,795 2,173 20.1% Medicine 120 Hemorrhoids 10,365 1,628 15.7% Medicine 62 Coagulation and hemorrhagic disorders 9,534 2,483 26.0% Medicine 134 Other upper respiratory disease 9,068 1,592 17.6% Medicine 234 Crushing injury or internal injury 8,329 1,224 14.7%

Medicine 201 Infective arthritis and osteomyelitis (except that caused by TB/STD 8,105 1,692 20.9%

Medicine 203 Osteoarthritis 7,984 1,061 13.3% Medicine 144 Regional enteritis and ulcerative colitis 7,954 1,601 20.1% Medicine 60 Acute posthemorrhagic anemia 7,768 1,588 20.4% Medicine 4 Mycoses 7,739 2,144 27.7% Medicine 126 Other upper respiratory infections 7,663 975 12.7% Medicine 143 Abdominal hernia 7,410 1,430 19.3% Medicine 139 Gastroduodenal ulcer (except hemorrhage) 7,378 1,117 15.1% Medicine 47 Other and unspecified benign neoplasm 7,123 1,286 18.1% Medicine 161 Other diseases of kidney and ureters 7,057 1,313 18.6% Medicine 121 Other diseases of veins and lymphatics 6,969 1,258 18.1% Medicine 232 Sprains and strains 6,531 895 13.7% Medicine 54 Gout and other crystal arthropathies 6,150 1,007 16.4% Medicine 84 Headache; including migraine 5,839 688 11.8% Medicine 147 Anal and rectal conditions 5,116 1,010 19.7%

Medicine 212 Other bone disease and musculoskeletal deformities 4,926 752 15.3%

Medicine 158 Chronic renal failure 4,886 1,196 24.5% Medicine 228 Skull and face fractures 4,632 596 12.9% Medicine 165 Inflammatory conditions of male genital organs 4,222 474 11.2% Medicine 52 Nutritional deficiencies 4,003 978 24.4% Medicine 253 Allergic reactions 3,885 575 14.8%

  DRAFT  50  

Unplanned 30-Day

Readmit Rate

Unplanned 30 Day

Readmits Model Group CCS Description Admits

Medicine 162 Other diseases of bladder and urethra 3,850 707 18.4% Medicine 137 Diseases of mouth; excluding dental 3,821 615 16.1% Medicine 164 Hyperplasia of prostate 3,734 684 18.3% Medicine 148 Peritonitis and intestinal abscess 3,663 909 24.8% Medicine 48 Thyroid disorders 3,634 669 18.4% Medicine 235 Open wounds of head; neck; and trunk 3,631 464 12.8% Medicine 241 Poisoning by psychotropic agents 3,191 411 12.9% Medicine 6 Hepatitis 3,042 830 27.3% Medicine 202 Rheumatoid arthritis and related disease 2,806 486 17.3% Medicine 8 Other infections; including parasitic 2,381 297 12.5% Medicine 236 Open wounds of extremities 2,253 356 15.8% Medicine 49 Diabetes mellitus without complication 2,198 316 14.4% Medicine 198 Other inflammatory condition of skin 2,028 424 20.9% Medicine 76 Meningitis (except that caused by TB/STD) 2,003 335 16.7% Medicine 248 Gangrene 1,996 438 21.9%

Medicine 90 Inflammation; infection of eye (except that caused by by TB/STD) 1,994 276 13.8%

Medicine 132 Lung disease due to external agents 1,866 378 20.3% Medicine 136 Disorders of teeth and jaw 1,602 194 12.1% Medicine 89 Blindness and vision defects 1,550 164 10.6%

Medicine 210 Systemic lupus erythematosus and connective tissue disorders 1,466 353 24.1%

Medicine 243 Poisoning by nonmedicinal substances 1,424 114 8.0% Medicine 3 Bacterial infection; unspecified site 1,386 261 18.8% Medicine 240 Burns 1,373 223 16.2% Medicine 77 Encephalitis (except that caused by by TB/STD) 1,361 242 17.8% Medicine 91 Other eye disorders 1,344 144 10.7% Medicine 175 Other female genital disorders 1,119 206 18.4% Medicine 225 Joint disorders and dislocations; trauma-related 1,104 129 11.7% Medicine 94 Other ear and sense organ disorders 1,005 117 11.6% Medicine 119 Varicose veins of lower extremity 991 139 14.0% Medicine 200 Other skin disorders 985 150 15.2% Medicine 167 Nonmalignant breast conditions 977 124 12.7% Medicine 257 Other aftercare 894 142 15.9% Medicine 168 Inflammatory diseases of female pelvic organs 852 139 16.3%

Medicine 87 Retinal detachments; defects; vascular occlusion; and retinopathy 852 84 9.9%

Medicine 142 Appendicitis and other appendiceal conditions 803 100 12.5% Medicine 209 Other acquired deformities 760 109 14.3% Medicine 156 Nephritis; nephrosis; renal sclerosis 756 201 26.6% Medicine 173 Menopausal disorders 748 117 15.6% Medicine 1 Tuberculosis 735 138 18.8% Medicine 64 Other hematologic conditions 730 149 20.4% Medicine 92 Otitis media and related conditions 724 105 14.5% Medicine 166 Other male genital disorders 714 150 21.0% Medicine 5 HIV infection 611 178 29.1%

  DRAFT  51  

Unplanned 30-Day

Readmit Rate

Unplanned 30 Day

Readmits Model Group CCS Description Admits

Medicine 247 Lymphadenitis 456 88 19.3% Medicine 249 Shock 451 112 24.8%

Medicine 9 Sexually transmitted infections (not HIV or hepatitis) 366 56 15.3%

Medicine 258 Other screening for suspected conditions (not mental or infectious) 328 41 12.5%

Medicine 217 Other congenital anomalies 312 59 18.9% Medicine 214 Digestive congenital anomalies 305 50 16.4% Medicine 170 Prolapse of female genital organs 257 52 20.2% Medicine 215 Genitourinary congenital anomalies 239 43 18.0% Medicine 124 Acute and chronic tonsillitis 221 10 4.5% Medicine 61 Sickle cell anemia 203 49 24.1% Medicine 57 Immunity disorders 158 54 34.2% Medicine 206 Osteoporosis 148 22 14.9% Medicine 10 Immunizations and screening for infectious disease 127 16 12.6% Medicine 88 Glaucoma 124 20 16.1% Medicine 172 Ovarian cyst 114 14 12.3% Medicine 208 Acquired foot deformities 103 17 16.5% Medicine 46 Benign neoplasm of uterus 102 15 14.7% Medicine 53 Disorders of lipid metabolism 98 16 16.3% Medicine 171 Menstrual disorders 68 11 16.2% Medicine 86 Cataract 37 6 16.2% Medicine 256 Medical examination/evaluation 30 5 16.7% Medicine 255 Administrative/social admission 14 2 14.3% Medicine 56 Cystic fibrosis 14 3 21.4% Medicine 169 Endometriosis 13 2 15.4% Medicine 174 Female infertility 1 - 0.0%

Medicine Total 3,009,835 549,935 18.3%

Neurology 109 Acute cerebrovascular disease 197,598 28,961 14.7% Neurology 112 Transient cerebral ischemia 82,499 9,272 11.2% Neurology 95 Other nervous system disorders 58,486 10,406 17.8% Neurology 83 Epilepsy; convulsions 38,034 6,115 16.1% Neurology 233 Intracranial injury 35,366 5,963 16.9%

Neurology 81 Other hereditary and degenerative nervous system conditions 10,075 1,797 17.8%

Neurology 110 Occlusion or stenosis of precerebral arteries 9,091 1,298 14.3% Neurology 79 Parkinson`s disease 6,651 921 13.8% Neurology 113 Late effects of cerebrovascular disease 6,396 1,062 16.6% Neurology 85 Coma; stupor; and brain damage 6,092 990 16.3% Neurology 111 Other and ill-defined cerebrovascular disease 5,316 638 12.0% Neurology 80 Multiple sclerosis 1,036 147 14.2% Neurology 82 Paralysis 883 135 15.3% Neurology 227 Spinal cord injury 832 144 17.3% Neurology 78 Other CNS infection and poliomyelitis 786 139 17.7% Neurology 216 Nervous system congenital anomalies 48 12 25.0%

Neurology Total 459,189 68,000 14.8%

  DRAFT  52  

Unplanned 30-Day

Readmit Rate

Unplanned 30 Day

Readmits Model Group CCS Description Admits

Psych 653 Delirium, dementia, and amnestic and other cognitive disorders 44,266 6,581 14.9%

Psych 661 Substance-related disorders 11,050 1,942 17.6% Psych 660 Alcohol-related disorders 8,578 1,270 14.8% Psych 657 Mood disorders 7,874 1,197 15.2% Psych 659 Schizophrenia and other psychotic disorders 7,849 1,253 16.0%

Psych 663 Screening and history of mental health and substance abuse codes 4,482 1,142 25.5%

Psych 651 Anxiety disorders 3,153 394 12.5% Psych 670 Miscellaneous disorders 1,315 207 15.7% Psych 654 Developmental disorders 594 123 20.7% Psych 650 Adjustment disorders 399 67 16.8% Psych 658 Personality disorders 127 21 16.5%

Psych 652 Attention-deficit, conduct, and disruptive behavior disorders 119 18 15.1%

Psych 656 Impulse control disorders, NEC 27 4 14.8%

Psych 655 Disorders usually diagnosed in infancy, childhood, or adolescence 16 4 25.0%

Psych 662 Suicide and intentional self-inflicted injury 10 2 20.0%

Psych Total 89,859 14,225 15.8%

 

 

 

 

 

 

 

 

 

 

 

 

 

  DRAFT  53  

Appendix D – Conditions that are treated as complications if occurring during index admission

CC  Label  Potential Complications 

2  Septicemia/Shock  x 6  Other Infectious Diseases  x 17  Diabetes with Acute Complications  x 23  Disorders of Fluid/Electrolyte/Acid‐Base  x 

24 Other Endocrine/Metabolic/ Nutritional Disorders    

28  Acute Liver Failure/Disease  x 31  Intestinal Obstruction/Perforation  x 

34  Peptic Ulcer, Hemorrhage, Other Specified Gastrointestinal Disorders  x 36  Other Gastrointestinal Disorders    37  Bone/Joint/Muscle Infections/Necrosis    43  Other Musculoskeletal and Connective Tissue Disorders    46  Coagulation Defects and Other Specified Hematological Disorders  x 

47 Iron Deficiency and Other/ Unspecified Anemias and Blood Disease    

48  Delirium and Encephalopathy  x 51  Drug/Alcohol Psychosis    75  Coma, Brain Compression/Anoxic Damage  x 76  Mononeuropathy, Other Neurological Conditions/Injuries    77  Respirator Dependence/Tracheostomy Status  x 78  Respiratory Arrest  x 79  Cardio‐Respiratory Failure and Shock  x 80  Congestive Heart Failure  x 81  Acute Myocardial Infarction  x 82  Unstable Angina and Other Acute Ischemic Heart Disease  x 85  Heart Infection/Inflammation, Except Rheumatic    92  Specified Heart Arrhythmias  x 93  Other Heart Rhythm and Conduction Disorders  x 95  Cerebral Hemorrhage  x 96  Ischemic or Unspecified Stroke  x 97  Precerebral Arterial Occlusion and Transient Cerebral Ischemia  x 100  Hemiplegia/Hemiparesis  x 101  Diplegia (Upper), Monoplegia, and Other Paralytic Syndromes  x 102  Speech, Language, Cognitive, Perceptual  x 104  Vascular Disease with Complications  x 105  Vascular Disease  x 106  Other Circulatory Disease  x 111  Aspiration and Specified Bacterial Pneumonias  x 112  Pneumococcal Pneumonia, Emphysema, Lung Abscess  x 114  Pleural Effusion/Pneumothorax  x 124  Other Eye Disorders    

  DRAFT  54  

CC  Label  Potential Complications 

129  End Stage Renal Disease  x 130  Dialysis Status  x 131  Renal Failure  x 132  Nephritis  x 133  Urinary Obstruction and Retention  x 135  Urinary Tract Infection  x 148  Decubitus Ulcer of Skin  x 152  Cellulitis, Local Skin Infection  x 154  Severe Head Injury  x 155  Major Head Injury  x 156  Concussion or Unspecified Head Injury  x 157  Vertebral Fractures    158  Hip Fracture/Dislocation  x 159  Major Fracture, Except of Skull, Vertebrae, or Hip  x 160  Internal Injuries    161  Traumatic Amputation    162  Other Injuries    163  Poisonings and Allergic Reactions  x 164  Major Complications of Medical Care and Trauma  x 165  Other Complications of Medical Care  x 166  Major Symptoms, Abnormalities    174  Major Organ Transplant Status  x 175  Other Organ Transplant/Replacement  x 176  Artificial Openings for Feeding or Elimination  x 177  Amputation Status, Lower Limb/Amputation  x 178  Amputation Status, Upper Limb  x 179  Post‐Surgical States/Aftercare/Elective  x 

 

 

 

 

 

 

 

 

 

 

  DRAFT  55  

Appendix E –Candidate risk variables

Label  Pope et al. CCs   Description* 

rf1  1, 3‐5  History of Infection rf2  6  Other infectious disease rf3  7  Metastatic cancer/acute leukemia rf4  8  Lung or other severe cancers rf5  9  Other major cancers rf6  10  Other major cancers rf7  11  Cancer rf8  12  Cancer rf9  15,16,18‐20, 119, 120  Diabetes mellitus or DM complications rf10  21  Protein‐calorie malnutrition rf11  25, 26  Liver or biliary disease rf12  44  Other hematologoical disorders rf13  49, 50  Dementia or other specified brain disorders rf14  52, 53  Drug/alcohol abuse/dependence/psychosis rf15  54‐56  Major psychiatric disorders rf16  58  Depression rf17  60  Other psychiatric disorders rf18  67‐69, 100‐102, 177, 178  Hemiplegia, paraplegia, paralysis, functional disability rf19  74  Seizure disorders and convulsions rf20  80  CHF rf21  83, 84  Coronary atherosclerosis or angina rf22  86  Valvular or rheumatic heart disease rf23  90  Hypertensive heart failure rf24  92, 93  Specified arrhythmias rf25  98, 99, 103  Cerebrovascular disease rf26  108  COPD rf27  109  Fibrosis of lung or other chronic lung disorders rf28  110  Asthma rf29  129, 130  End stage renal disease rf30  149  Decubitus ulcer or chronic skin ulcer rf31  2  Septicemia/Shock rf32  22, 23  Disorders of fluid, electrolyte, acid‐base rf33  47  Iron deficiency rf34  79  Cardio‐respiratory failure or shock rf35  81, 82  Acute coronary syndrome rf36  95, 96  Stroke rf37  104, 105, 106  Circulatory or vascular disease rf38  111, 112, 113  Pneumonia rf39  131  Renal failure rf40  136  Other urinary tract disorders rf41  148  Decubitus ulcer  

 

  DRAFT  56  

Appendix F – Final risk-adjustment variables

Label Pope et al. 

CCs Description* 

Not adjusted for if only present on index 

admission (complication) 

Age  n/a  Age (‐65)   Cond. Ind. 

n/a  Condition indicator (AHRQ CCS)   

rf1 

1, 3‐5  Severe infection   

1  HIV/AIDS   

3  Central nervous system infection   

4  Tuberculosis   

5  Opportunistic infections   

rf2 

6, 111‐113  Other infectious disease & pneumonias   

6  Other infectious disease  x 

111  Aspiration and specified bacterial pneumonias  x 

112  Pneumococcal pneumonia, emphysema, lung abscess  x 

113  Viral and unspecified pneumonia, pleurisy  x 

rf3  7  Metastatic cancer/acute leukemia   

rf4 

8, 9  Severe cancer   

8  Lung, upper digestive tract, and other severe cancers   

9  Other major cancers   

rf6 

10, 11, 12  Other major cancers   

10 Breast, prostate, colorectal and other cancers and tumors 

 

11  Other respiratory and heart neoplasms   

12  Other digestive and urinary neoplasms   

rf9 

15,16,18‐20, 119, 120 

Diabetes mellitus    

15  Diabetes with renal manifestation   

16 Diabetes with neurologic or peripheral circulatory manifestation 

 

17  Diabetes with acute complications  x 

18  Diabetes with ophthalmologic manifestation   

19  Diabetes with no or unspecified complications   

20  Type I diabetes mellitus   

119 Proliferative diabetic retinopathy and vitreous hemorrhage 

 

120  Diabetic and other vascular retinopathies   

rf10  21  Protein‐calorie malnutrition   

rf11 25, 26  End‐Stage liver disease   

25  End‐Stage Liver Disease   

  DRAFT  57  

Not adjusted for if only Pope et al.  present on index 

Label  Description* CCs  admission 

(complication) 

26  Cirrhosis of Liver   

rf12  44  Other hematologoical disorders   

rf14 

51‐52  Drug and Alcohol disorders   

52  Drug/alcohol dependence   

51  Drug/alcohol psychosis   

rf15 

54‐56, 58, 60  Psychiatric comorbidity   

54  Schizophrenia   

55  Major depressive, bipolar, and paranoid disorders   

56  Reactive and unspecified psychosis   

58  Depression   

60  Other psychiatric disorders   

rf18 

67‐69, 100‐102, 177, 178 

Hemiplegia, paraplegia, paralysis, functional disability   

67  Quadriplegia, other extensive paralysis   

68  Paraplegia   

69  Spinal Cord Disorders/Injuries   

100  Hemiplegia/hemiparesis   

101 Diplegia (upper), monoplegia, and other paralytic syndromes 

 

102  Speech, language, cognitive, perceptual   

177  Amputation status, lower limb/amputation   

178  Amputation status, upper limb   

rf19  74  Seizure disorders and convulsions   

rf20  80  CHF  x 

rf21 

81‐84, 89, 98, 99, 103‐106 

Coronary atherosclerosis or angina, cerebrovascular disease 

 

81  Acute myocardial infarction  x 

82 Unstable angina and other acute ischemic heart disease 

x 

83  Angina pectoris/old myocardial infarction   

84 Coronary atherosclerosis/other chronic ischemic heart disease 

 

89 Hypertensive heart and renal disease or ensephalopathy 

 

98  Cerebral atherosclerosis and aneurysm   

99  Cerebrovascular disease, unspecified   

103  Cerebrovascular disease late effects, unspecified   

104  Vascular disease with complications  x 

105  Vascular disease  x 

  DRAFT  58  

  DRAFT  59  

Label Pope et al. 

CCs Description* 

Not adjusted for if only present on index 

admission (complication) 

106  Other circulatory disease  x 

rf24 

92, 93  Specified arrhythmias   

92  Specified heart arrhythmias   

93  Other heart rhythm and conduction disorders   

rf26  108  Chronic obstructive pulmonary disease   

rf27  109  Fibrosis of lung or other chronic lung disorders   

rf29  130  Dialysis Status  x 

rf30 

148‐149  Ulcers   

148  Decubitus ulcer    x 

149  Decubitus ulcer or chronic skin ulcer   

rf31  2  Septicemia/shock  x 

rf32 

22‐23  Disorders of fluid, electrolyte, acid‐base   

22  Other significant endocrine and metabolic disorders  x 

23  Disorders of fluid/electrolyte/acid‐base  x 

rf33  47  Iron deficiency  x 

rf34  79  Cardio‐respiratory failure or cardio‐respiratory shock  x 

rf39  131  Acute Renal failure  x 

rf40  32  Pancreatic disease   

rf41  38 Rheumatoid arthritis and inflammatory connective tissue disease 

 

rf42  77  Respirator dependence/tracheostomy status   

rf43 

128, 174  Transplants   

128  Kidney transplant status   

174  Major organ transplant status   

rf44  46 Coagulation defects and other specified hematological disorders 

 

rf45  158  Hip fracture/dislocation